What do you teach incoming kindergarten?
Sing, read, and talk about the alphabet. Talk about colors and shapes. Count numbers up to 30, and even sing about them. Teach your child his/her full name, parent's names, and phone number.

https://www.scholastic.com/parents/school-success/school-life/grade-by-grade/preparing-kindergarten.html?fbclid=IwAR1uhAzkjHNJsjwPYeOETBlU-S2J323kjLcgo2qdXuyzcW7ImvkCPx8AGtc&fs=e&s=cl