I'd been "planning on building a game" for probably a decade. Pico-8 got me to finally "finish" a few. The integrated graphics and audio system is super useful for cobbling something together.
More important than any particular route you take is merely sticking with it. The choice of game engine doesn't matter that much as long as you make and finish games with that engine. Everything else is secondary and mostly procrastination.
After there is the big engines, Unity, Unreal, and Godot. They all have their ups and downs, but are the next level of complexity up from the previously mentioned tools.
If you're into specific niches there are sometimes purpose built engines for it, like RPG Maker. They are usually much less complex, albeit limited to specific kinds of games.
This is a popular enough way of doing it that it exists for most of the popular engines. Unity just tends to have the most.
You can start here: https://www.youtube.com/watch?v=j48LtUkZRjU&list=PLPV2KyIb3j...
Using a game engine like Unity you can create something pretty advances in a short time. There are tons of tutorials on YT. If you prefer a free game engine, check out Godot.
If you're looking at doing it "from scratch", you should really consider starting out small with something like Pong or Tetris. The best resource I know is Handmade Hero for that, tons of YT videos and huge community.