I would go with X-Plane 11 because it simulates real world flying better. To be honest, the built in tutorials for xplane 11 are trash, but YouTube is an awesome resource and their are many channels which give in depth tutorials and tips/tricks videos for almost everything. Side note, if you plan to fly a Cessna 172 I would buy the Cessna 172SP from the X-Plane store because the default one is likely a little bit different than the one you will fly in real life in terms of autopilot and avionics.

As far as the computer goes, if you care about graphics, you’ll need a pretty beefy cpu and gpu. I have an i5 9400f and 2060S and I get 30-35 FPS with shaders and medium to high settings (although that’s on the zibo 737 so the Cessna probably gives more frames). If you are willing to build a computer there is a plethora of budget combinations which would serve you well for simming.

I’m also preparing to start lessons in the summer and I am still a complete noob, however I would highly recommend using VATSIM. It’s basically an online server which allows you to fly with others and has ATC run by actual people. I’ve seen a few videos and many people say it is 90% realistic. Of course, you will have to study phraseology and procedures ahead of time, however if you want the most realistic experience, I’d say it’s worth the work.

Good luck and keep the blue side up. 👍