I've seen some other projects on the forum here, to do what you want to do. In general, I'm against using a complex architecture to do a simple task. For example, my HVAC unit has an 8 bit MCU for control. It hasn't done anything wrong, nor has it reset in 15 years.
Cuz it's simple.
That said, if you decide to operate your garage door with a complex architecture that has bugs and may run the door down on your cat, then there's no-one to stop you.
If I were doing this sort of thing (even tho I would just use the simple device that came with the door) - I'd probably opt for a device that's between a Pi and an 8 bit MCU. The Photon from Particle.io comes to mind, as it has built in WiFi, and is fairly cheap (about $20). It's the size of a USB stick. It's more complex than the 8 bit MCU, but a lot less complex than the Pi. But this IS NOT advice. Don't say I told you so, cuz the Photon's program can go over the wall as well as the Pi's, with the level dependent on the coder's skill. You say beginner, so that's kinda a red flag. Also, with WiFi there's the possiblity of hacking. Not trying to be insulting, but there's your cat to worry about. Really, what benefit do you perceive other than a fun project?
Also, the Photon itself could have bugs due to it's still being in development.
I am the Umbrella man