Suz is right. He does not need to know how to read, write or do much of anything! That's what kindergarten is for! Preschools that push academics just avoid doing what's really necessary, and they put pressure on kids and parents!
Kindergartners need to be able to separate from Mommy and Daddy, and see their teacher as the loving authority figure. They need to follow directions, be able to sit in a circle, and negotiates their own space without whacking the hell out of the kid next to them. They need to be mature enough and have enough socialization that they can work in a group. That's all! A friend of mine is a kindergarten teacher, and she would much rather have agreeable kids who don't know how how to write their names than academic robots who can't function in a group! She even puts a strip of masking tape down on the floor because they don't even understand how to line up yet!
If your son has been in preschool, he already understands about going to different "station" for different activities - circle time over here, arts & crafts over there, put your coat in the cubby in this corner, wash up after snack, and so on. He has experience with a teacher, and with having a room full of other children, and existence of other classes that are doing different things at the same time. He understands that there is breakfast, getting dressed, going to school, and then home again.
The most important thing is that you relax! Your child does NOT need any stress about this, and he will pick up on your anxiety. You have to be sure that he is emotionally and developmentally ready to start school at 5. If not, he simply has another year of preschool and starts at 6. It is NOT about how smart the child is! Never make that mistake!
There will be a kindergarten screening of some sort - he will probably meet with one of the teachers (you will attend) but not necessarily his future teacher. That is okay. They ask some questions and have him do a few simple things, and they assess his readiness (NOT his intelligence). You will get a notice for this. They will probably have an open house or orientation of some sort, when he and you will get acquainted with the building (just his wing) and see a few classrooms. It's essential that he not be made to believe that he must know everything that will happen in the course of the day.
If he is to take a bus, there will be some provisions for first-time kids. In our district, the kids all get a tag to tie to their backpacks, which has their name and their bus route and their classroom on it. There are aides on the buses, and kindergarteners sit in the front seats unless with an older sibling. The buses are greeted by teachers or aides, and the kids are lined up for the correct classrooms, either at the drop-off point or in an indoor location such as the cafeteria. You will get a list of what they need to bring and what they do NOT need to bring. Follow this list. Do not make it more complicated. Do not go out to buy school supplies or fancy clothes - you will get a list of what's needed (not much on Day 1) and you want him in comfortable play clothes for normal daily functioning.
I suggest you NOT call the school until things get closer - trust that there is a program in place and that you will be notified. I also suggest that you not keep talking about "kindergarten next year" with him until you are assured, by the preschool, the kindergarten screener and your own gut that he is ready. My son was NOT ready (not good at following directions to some degree, but mostly he was a supreme afternoon nap-taker and could not have handled school being that tired). We held him until 6 and never regretted it.
And I agree you should not be listening to every other parent out there about what you MUST do to get him "ready"! Too much pressure!