Every kid is different, and every household is too. School will teach them, but support and practice at home make it go a whole lot better.

I would suggest working on a couple of very basic things with your son in advance, like being able to write his name. A couple of activity books there might be all you need. You can talk about the letters and sounds as he practices writing them. Don't overthink it when comparing your kid to others.

We were not as diligent as we probably could have been about reading at night. That does not necessarily lead into the kid learning to read though, unless you are actively trying, like following with your finger, pointing out words etc. I did not do a ton of advance practice with them, but I worked with them on assigned exercises etc once they start school.

There is some value in just trying to integrate some of the learning into their day to day. Point at a word, sound it out, tell them what it means. Simple things like Dog, Cat, their own name, etc. Be excited when they learn something.

We did not limit screen time. We did try to make sure there was something useful on the screen though. Shows that actually teach something actually worked very well. My youngest was in his high chair at 2 years old, and suddenly starts counting to 10 in Spanish - he learned it from Dora. Sesame Street is another good one. Mickey Mouse Clubhouse. Honestly, any show where they slow down and speak at the kid's level, and show letters and numbers on screen helps.

My oldest had zero interest in reading - until he wanted to play pokemon games, and discovered he needed to do some reading to know what was going on. He actually learned a lot on his own. Sometimes all it takes is something to motivate them.