You might be better off posting in Primary Education- lots of helpful people there.
It sounds as though he just isn't ready for reading yet. Don't forget that we start formal education very early in the UK compared to other countries. Try to keep things as relaxed and fun as possible, and don't compare with other children too much- late starters will often overtake their peers later on.
A few ideas to try (sorry if you've already done a lot of this!)
Read a book together- ask your DS to find just 2 words on each page that will be 'his' words, while you read all the others. Gradually increase 'his' words.
Scatter a set of magnetic letters or letter cards on the floor. You say the sound, he has to find the letter- how many can he do in one minute? Move on to digraphs (sh/ch/th/oo etc) when he is ready.
Write him a 'secret message' to read when he gets up in the morning, on a whiteboard or even in a sealed envelope. It can be really simple, a message about the day works well- 'We can go to the park today'. But you do need to think quite hard about using only words he can read.
Try playing pairs or snap where one card has a picture on and the other has the word- quite a lot of cvc words can be linke to simple pictures e.g. cat, dog, hen, man etc.
I like this phonics site for games, it's a subscription one, but there's quite a lot of free games as well. Another one that worked well for my daughter is Reading Eggs. It was really good for the early stages of reading and very motivating, but I'm not so keen on how it works later on- it strays away from phonics too much for my liking.