Give him time . My boy wanted to do nothing but stand at 4 month then 5 months he suddenly started sitting and by 8 months he decided he wanted to roll both ways Everything with my boy has literally happen over night out of the blue
Some kids skip the crawling phase and just scoot or roll then walk. But give it time. My oldest didn’t crawl until 9 or 10 months old
Also my middle child walked at 9 months old. Some babies walk earlier too.
My little one was the same I just done a little bit more tummy time xx