or do something I'll be able to enjoy
I won't have the time or the energy for a hobby especially for one as demanding as this
Did not sound to me, as you enjoy creating games. If you were enthusiastic about it, you would just finish the game and not ask for advice on the internet if you should do it.
You seem to make something like that:
https://itch.io/games/top-sellers/tag-roguelike/tag-top-down-shooter
If you filter for paid, you will see, that only 60 of those 80 games ever sold anything.
To guess how many sales were made, you might look at the ratings and the followers. You can also guess by looking at https://itch.io/games/on-sale . That will not tell you how many sales the game makes overall, but it will tell you a general magnitude.
So, you should be able to guess what a hypothetical game might generate. Just look at a similar game. The problem is, that you do not know if you would be able to create such a game. And more importantly, if you would be able to successfully market it to the people willing to pay for the game. The market for games is saturated. Creating a game is not enough.
If you have never created a game, you do not even know if you can do it. That is not a textbook homework in coding. Even if you toiled away for months from morning to night, the result might be ... just not be any good. At least not in a way, that people would be willing to pay for it.
You are on Itch. Have a look at game jams. And finish a few games, before you decide to try doing this full time. Or even as a hobby. You did not even finish your first game. That really does not sound to me, like you really enjoy game making.