Start with high-confidence alphabet books books, then narrow by subgenre or adjacent topics.
Pete the Cat 12-book Phonics Fun!
James Dean, Kimberly Dean
Bob Books - Set 1: Beginning Readers Box Set of 12 Paperbacks | Decodable Phonics Books, Ages 4 and Up, Kindergarten (stage 1: Starting to Read)
Bobby Lynn Maslen, Amy Jindra
Chicka Chicka Boom Boom
Bill Martin Jr., John Archambault