Getting a job at 15 is going to be very difficult. A lot of employers try to avoid hiring anyone under the age of 18, because minors bring with them all kinds of extra state Department of Labor rules and OSHA regulations, such as longer/more frequent break periods and types of work that you are allowed to be assigned, as well as the fact that it can be a major hassle to have to schedule around someone's school schedule. If you're set on trying to get a job though, then by all means do not let that discourage you. Just know that you are in for quite the hunt.
As far as getting a job that doesn't suck, as was mentioned before, as a (presumably) unskilled 15 year old (you presumably have no certifications, no college degree, not even so much as a high school diploma or equivalent, or prior job experience) prepare yourself to start small and work your way up. Not all companies are worth taking promotions, because you get a boatload of added responsibilities for pennies more an hour. But ones do certainly exist as well that have advancement opportunities that are worth taking. What I would personally recommend if those computer repair shops don't pan out - look into warehouse work. Depending on whether it's a small or large scale operation, you could become the local "computer guy", not really getting paid any more but you have found yourself working with all of the computer systems in the building, or some companies, actually hired into the building's IT department. Warehouse work in general usually isn't -terrible- either, as long as you do what you are supposed to be doing and don't fuck around too much, generally you won't run into many issues.
This is all not taking into account NY state's minimum age to work.
https://www.labor.state.ny.us/workerprotection/laborstandards/workprot/wptypes.shtm you have to get a permit to be able to work. Warehouse work, you might not be able to do until you are 16. There is a newspaper carrier permit that you could get though, if that is an option.
Long story short though, IMO you are at a position in your life where you shouldn't worry so much about trying to build a career, but instead, not worry at all. I think you'd be best suited enjoying your childhood while you've still got it. You've got all of your adult years ahead of you to worry about stuff like this. But if you do want to press on and try to get a job, don't focus on doing something you love. Do anything, stick to it to show that you can commit to something and be responsible. Use it to pad out your resume a bit, and at the same time, make a little bit of spending money.
Problem with this is that internet cafes aren't so common here in the US.