Since the OG Backpage went down, over time sites have popped up with similar names, hoping to capitalize on name recognition.
Just looking now there's bedpages (multiple of this name, with different domain endings), 2backpage, yesbackpage, backpageclassifieds etc...
If you have the specific link it might be easier to say if legit or not?
But in my personal experience in my area, Leolist is (undeservedly) #1, megapersonals and tryst coming in behind, and a few free sites to post on (but they tend to attract a sketchier crowd)...it's been a while, but last I checked no one really uses the Backpage clones, all the posts were generic scam ads with stolen pornstar pics.