Practice

Learn to read theory

Use a metronome

Ignore drugs

Learn simple songs and build from there

Be patient to build callouses and finger strength

t.carpal tunnel

Start making noise.

Set yourself some goals in terms of what you want to do with it.

I found playing along to simple songs was so much more enjoyable than playing scales to a metronome.

What if i can not concentrate me longer than 30 second and my short-term memory doesn't work? Its still possible to play guitar for me?

You can improve your concentration powers through practice.

I can't. I'm disabled.

Drugs!

 

Not sure if you're already on any meds, or have been given any sort of diagnosis, but drugs like Adderall (for me specifically Vyvanse) really help the mental fog. It's wild how effective it is.

Don't listen to the drug addicted burger. Drugs will only temporarily boost your concentration until you're faced with the task of navigating around the no drug issue.

 

Don't be stupid. Go outside. Get off the internet, figgit

I find if I am enjoying something then I can concentrate for longer. That said, most of the time I pick up my guitar I just randomly noodle and make strange noises rather than practice.