When do babies usually turn over or crawl?

My dr told me at my 2 month appointment babies should be rolling over by 4 months.

My son started rolling over at 8 weeks and crawling at 6 months my daughter rolled over at 9 and a half weeks but crawled at 6 months

6-12 weeks depending on if the parents are active earl crawlers means baby’s is moving out the way

My son started rolling at 3 months I think and started crawling at about 9 months.