GT Avalanche or something else?

I am looking for a bike I can use on the street and for occasional mountain biking! I am still a newbie so I have been looking on facebook marketplace for a decent bike and while there are a TON of options, I cant find many with a small/xs frame! (27.5 inch inseam & 5’0)
I came across one bike that might be suitable frame size wise (GT avalanche) but I’m not sure if its suitable for both road and trail. If anyone has advice please let me know!