Advice needed for teaching my 4-year old son how to read

He’s almost five and I feel like I haven’t been helping him as much as I should’ve. I assumed he would get help in daycare (late birthday) but he only knows how to sing the ABC’s and couldn’t tell me what the letter A was called or sounded like. I read him books every night to get him interested in books. His favorite so far is Dragons Love Tacos.

I also bought the first set of BOB books but he doesn’t seem to get it. Is this just something I should stop and try again in a few months and just keep reading before bedtime like I have been? Or is there a better method I should try? There’s a book called “Alpha-Phonics: A Primer for Beginning Readers”, but I’m not sure if that would be any better than the BOB books.

I’d appreciate any advice from fellow dads who’ve taught their kids how to read.