Some Thoughts
Our students entering K come with a wide range of skills. Some have never been to preschool, while others have had 2-3 years of preschool. Recognizing his name, recognizing the letters in his/her name (especially since he has a long name), knowing some letter sounds, being able to write some recognizable letters and numbers (not necessarily written perfectly and written without guidelines), drawing straight and slant lines, being able to copy shapes, drawing a 6 part person, oral counting to 10, and having one-to-one correspondence would all be developmetally-appropriate for entering kindergarten.
We tell our preschool teachers to focus on things like oral language development, gross motor skills, fine visual motor skills (not formal handwriting), visual and auditory discrimination, phonemic awareness, social emotional skills, things like being able to listen to a story being read, following simple directions, attending to a task, waiting for a turn, sharing, and self-help skills-especially toileting skills. The academic skills will come if these precursors are already in place.
Those precursors are important. For example, If a child has weak core muscles, he will have difficulty sitting and may have difficulty with attention because of having to shift position frequently. If a child has weak fine motor muscles, he will have difficulty holding and controlling a pencil. Iif a child has weak visual motor, he will have difficulty copying letters. numbers, and words. If a child has weak visual discrimination skills, he will have difficulty distinguishing between letters. If a child has weak auditory discrimination skills, he will have difficulty distinguishing between sounds. You get the idea why these are important.
I have students who enter K not knowing any letters or sounds, but catch up to the rest of the class once they are exposed to them because all the precursors are in place.
Can you check out what the standards are for the kindergarten that he will be attending and work from those? Sometimes they will show the prerequisite skills needed before doing that grade level or a district's website might share expectations for entering kindergarten.