Keep an eye out for special offers, e.g. I bought an "ultimate" bundle (which includes everything) back in Feb 2021 which includes future updates.
However, I would also recommend making as many small (tiny) games as you can. There's nothing as motivating as releasing something often. You have to be diligent, though, and not succumb to scope/feature creep. There's nothing like learning by doing.
PS check GDQuest's "recommended" channels at the bottom of their YT channel for more good stuff.
I have experience way back with Unity and this has been getting me up-to-speed with the Editor/Engine. It uses GDScript, but I've been following along with C# just fine.