A favourite song and general life philosophy
With that in mind then what I am about to say may be cast in a different light.
Anyway your parents would likely have taught you or caused you to learn most things here if they had done a good job. Classic ones are cooking, cleaning, washing clothes, managing money, fixing basic things, sorting your taxes, maybe driving if you live in a place where it is necessary (I have been in various parts of the US and it is not easy)... in days of old many girls would have a so called bottom drawer that they accumulated stuff they would need when they got their own house.
Some will take a slower approach and go to university or something first. This eases some things as it gives you some responsibility for looking after yourself but keeps you coddled in other ways. If you are not doing university or similar some will continue to stick around but making their own food, sorting stuff for themselves and otherwise.
"find a mate"
You don't have to do that and it is not necessarily part of being a mature and responsible adult. For some it will happen almost by accident. Others will have to work at it. Others will say forget it and do their own thing. It can be useful when doing the mortgage thing as you have two combined incomes and can reduce overhead a bit. At least until you split/divorce (first marriages are about 50% divorce rates these days -- not odds I care to gamble with).
Going further.
You will want a place to stay you have three main options, though lines blur a bit.
1) Living out of a vehicle or something.
2) Renting a place (be it hotel, house or something more like 1).
3) Buying a house, outright if you can but most will probably get a mortgage or loan.
The modern world is rather difficult for a lot of people (it not like wages have necessarily increased since the 70s, housing has gone up somewhat though) so you need to calculate what your income is (be it from a job, from investments, from trust funds, from some nice government handouts...), is likely to be and what you can afford. To that end many do kit out a van or something and live in that to save up enough money to do something else with.
Renting in the eyes of some is wasted money, and on the face of it you are more or less just paying someone else's mortgage. I would say it depends upon how you do the maths, and what you value in life -- I like the ability to drop everything and sit halfway around the world, or move to another/across the country which is harder when you are stuck with a house you have to sell first. Also depending upon the ratio of rent to mortgage payments, and whether you fall for that nonsense that is "starter homes" if you stuck the difference between rent and mortgage is a proper investment account now and continued adding to it then by the time you come to retire you could have a comparable fund to someone what has sold their final house and is looking to do the whole dementia bit in a nursing home.
Similarly you can pay your parents some rent if you want that -- most people appreciate a bit of extra income and for many then better your parents than some faceless corporation.
Anyway onto calculating whether you can do it. Mortgages vary around the world but generally 4 and half times annual salary on top of some reasonable credit works well here, the amount you will need to cough up as a deposit varies but 10% is a good start (lower ones tend to make for far more expensive mortgages) and 20% is even better. Parents, grandparents and such often help with the deposit. Recall the earlier thing about wages -- 4 and a half times most annual salary around here buys you a run down shack and it is a similar story in a lot of places.
Or if you prefer
https://www.indeed.com/salaries/Cashier-Salaries-at-Safeway?period=yearly says just over $21000 for a shelf stacker/cashier at safeway which means your would be house gets to cost $100000 or so, and you will need to save up say 10000 of that (rent on a studio apartment/flat in new york city is some $15000 a year -- now you know why many people have house mates).
This is why some will try to gain a trade of some form, oh and the cost of that can also change how things play out here; $10000 a year for four years of a public in state US college, probably plus a bit more to round it out, all of which has to be paid back on top of your mortgage and they will find you for that one. US college for a lot of things is a dubious proposition these days so many are opting for trade schools instead -- a proper one of those will see you earning at the same time that you are learning.
If you do fancy the buying a house bit I find it far easier to know what to look for but if not then bring someone that does. Your location says New York so if that is city good luck with that one, state is not that much better. Do remember that a 50 year lease when you are 20 only takes you to 70 and many people live a lot longer than that (how old are or did your grandparents, great aunts and uncles and such live to?), though New York City is probably one of the three places in the world I would outright buy a flat in (London and Tokyo being the other two).
"I know not everyone even at adult age has left their parents yet which I do not cast shame upon and you shouldn't feel bad"
The whole kick 'em out as soon as they turn 18 thing is a rather US mindset, one I find both amusing and disturbing. At one point there was lots of land and houses but people were content to continue doing the three generations in one house thing so advertisers, marketers and such came up with the idea to try to sell more houses. Another trick is that starter home thing I was on about earlier.
" to living without their [parental] support"
You don't have to chuck them your keys and say see you at weddings, high days, holidays and funerals. Many times they will be able to help with deposits for renting/mortgages, furniture (if they want to upgrade you might be able to have/buy on the cheap their old stuff that you probably already know), maybe help with a vehicle, health insurance if that is a thing around you (most places will have things that say you can continue on their policy until you are 25), maybe a phone bill, will allow you to tack on things to a big shop (them and you both pooling needs to buy in bulk makes thing a bit cheaper)...
Short version. You gonna need money. Figure out a way to get some, and then get some more and continue doing that until the day you die (or were lucky enough to be able to save some so that when your body starts to fail you can afford to sit around doing nothing all day). People pay more for rare and hard to come by skills, especially if they are dirty, demanding or dangerous, so if you can then consider some of those. Other skills are useful (bottom two rungs of
https://www.simplypsychology.org/maslow.html ) so make sure you can do them as well -- paying people to do it for you is possible but every time someone does something it will add more to the cost, to that end to live cheaply I recommend knowing how to do it all.
