My son won’t say his Abcs and he’s almost 5

I am panicking my son is almost 5 years old on the 13th of this month and going into kindergarten in September. He will not say his ABCs with me or my husband or count numbers with us he just thinks it’s a joke. It’s almost like he is embarrassed or gets nervous. I am scared hes going to go to kindergarten and they are going to blame me and think I am a horrible mom 🥺 He is so HARD I always feel guilty like I don’t do enough and that I am failing him. I have practice books and cards but he just will NOT take it seriously. Please tell me that this is not just me