I hear your frustration and understand what you're concerned about.

Ask yourself this.

Is the thing that I've discovered is broken today something that I've fixed before?

If you use the package manager that comes with your distribution and don't install random software from the Internet, and don't follow unverified procedures written by anyone with a keyboard, then the answer is almost certainly "no".

I say this with the benefit of knowing what's good practice and what isn't. I can tell you that if you come at this with a "Microsoft Windows" approach, you're likely to spend weeks, if not months in purgatory. It's no different from migrating between MacOS and Windows, or vice-versa. You need to remember that just because Linux looks similar, it's a different beast and is so by design.

I'd strongly recommend that you start using the machine with ONLY the packages available through the Ubuntu package manager. If you run into strife, you can ask for support. If you go outside that and you break something, you get to keep both parts -- and truth be told -- that's true with any other operating system, just that the lines are not as blurred.

In Linux world many of the distributions can cross pollenate applications and solutions, but that requires experience that new users don't (yet) have.

One way to deal with the "jump" is to keep your "old" Windows (or MacOS) machine around while you get comfortable with the lay of the land.

The thing that most people switching to Linux have forgotten is that this requires experience. You cannot expect to just jump into a new Operating System and take all your old habits with you. Think for example about the differences between iOS and Android, a world of difference.

So, keep at it. This frustration will pass.

Make sure you backup your /home directory regularly. That way if you ever blow something up and are left on your own, you can blow away the drive and start again, restore from your /home backup.

Meanwhile, keep asking questions.

Good luck.