It depends what you want to do and where you care to end up -- it is far nicer to grow into a program's limits than outgrow a program and have to learn a new one for me. At the same time if you learn one you should be able to adapt fairly easily to another. I should also note variable resolution, variable frame rate does not really exist (technically it does but nothing other than a specially configured PC will likely play it back) so if you are going to start mixing and matching different resolutions and framerates it instantly makes it harder and as the problem is one of those "quick, good quality, easy -- pick two" things then yeah. It is not so bad if you just want to stitch footage from the same settings on the same camera together but as we are on a gaming forum I will assume you will eventually get into wanting to capture footage from old consoles or something, wherein not everything will be the nice 1080p30 of a basic camera. It is all relatively easy to sort but still can be a pain.
Oh and while audio can be kicked out of a video, cleaned up/altered/additionally dubbed in audacity and brought back in to things it is another layer of complexity for some.
There are plenty of very basic video editors that will allow you to chop bits out and stick things in a different order if you so desire. This would be 95% of what most people need for video, especially as many of said same will also do captions/subtitles well enough and title cards and such made with static image editors can be added in just as easily as video clips.
Start adding in colour grading, proper noise reduction, motion enhancements, overlays (think sticking your webcam in the corner of a shot) not so much but tracked overlays definitely, really fancy animated transitions (some of the simpler editors might come with a bunch of prebaked ones) and you start making things harder, keying (greenscreen) is also often in the higher end.
There are three major work flows within video (we will skip the linear vs non linear editing aka NLE for now as most things these days are functional NLE).
Conventional simplistic. Here you will open a video, append a video, chop/trim bits accordingly and go from there. This is the last real vestige of linear editing that most people are likely to encounter but functionally it is not linear editing. Virtualdub
http://www.virtualdub.org/ (normally used for capturing or basic conversions of things) has abilities here,
http://avidemux.sourceforge.net/ is another such thing.
Timeline based. What many higher end things will go for including most of the big commercial offerings, and things looking to ape those will do.
On the free front windows is somewhat lacking here, Linux (its lack of video editing abilities at one point something of a joke might well have snuck up and overtaken it here) on the other hand does fairly well.
https://kdenlive.org/en/download/ for the linux and beta windows main starting point, though
https://itsfoss.com/best-video-editing-software-linux/ also does well.
I have used lightworks in the past. It did very well for "freemium" software in that it was not crippled and actually could get something done but limitations on output mean I will steer clear if I can.
https://filmora.wondershare.com/video-editor/free-video-editing-software-windows.html if we are doing windows.
If you want to start paying then you have more options. Adobe's Premiere being what many in the hobby and lot of professional world (the silly money pros have other tools) look to, especially when it also comes with after effects which does all the fancy effects work for a lot of people. Magix's (formerly Sony's) Vegas software, and Apple's Final Cut family being the other big choices in the lower end (but still quite expensive for the average pleb, especially if you want to buy a mac to use final cut) market. I will throw in DaVinci Resolve in there because I have to. There are mid tier commercial things that usually get bundled with cameras, dvd burners, computers from vendors and such, many of them enjoy considerable usage among the youtube video set.
Clip based. What my preferred editor (avisynth
http://avisynth.nl/index.php/Main_Page and derivates) go for. Avisynth is script based though so some don't get on that well with it and in some ways the initial learning curve. Here is an older thread of me toying with things
https://gbatemp.net/threads/be-a-great-video-maker-and-replicate-this-video-effect.360509/