Yes, if your son asks the court for an attorney they'll get him one, someone would have to pay for it so I don't know how that will work out.
Yes, your son can go to court and request he get to live with his dad. IF IF IF dad is doing nothing illegal and has no charges against him son will likely get to go live with dad.
Happens all the time. Kids do have a say in where they live. My niece went at age 8 and told the judge she wanted to live with her dad because she didn't want to be a Jehovah's Witness. Judge gave custody to her dad. Mom paid child support too. She was working as a cashier in a grocery store living in an apartment large enough for her daughter to have her own room when she came over to stay, which was a lot of the time, and my sister was making minimum wage. It was extremely hard but she was in her 40's and hadn't even graduated high school. She eventually became the apartment manager and worked her way up to where she is now running her own Etsy business.
Another girl I know is 10 and the judge, same state, won't hear her until she is 12. So it depends on the city, county, and state as to when a judge will listen to him.
The judge won't side with you if it's "His dad is more permissive than I am". He'll look at you and think "poor kid".
Perhaps you need to lighten up on your son. I don't know what your rules are but you seem to be pretty focused on "you must obey rules" so it sounds like there might be a lot of them.
If you limit his computer time...why? Is he behind in school work? Does he do his chores then sit around all evening wanting to be on the computer? Why can't he be on it?
Is he basically a good kid? Is he in trouble all the time? Get grounded off the computer?
Does he go to bed at an unreasonable hour? At dad's they let him stay up until he's tired? Does he still get up and go to school? Perhaps he is older and doesn't need to go to bed so early?
My basic point is that kids will go where it's easiest and that doesn't always make it a good place or bad place.
Kiddo WILL get to be heard and if they judge sees no LEGAL reason to deny the request kiddo WILL go to dad and YOU'LL find yourself with visitation and paying child support.
So which is worse? Lightening up on the kiddo or having him living with dad?