The comment above is correct! The risk of SIDS greatly decreases once baby is able to roll both directions. They’ll either roll back over or cry for you to give them a hand
If it helps you feel better, get an Owlet or a Snuza. Our little girl basically sleeps on her tummy every night now once she figured out how. We were stressed AF the first week but I'm adjusting to it, but feel so much better having a monitor on her. We were using the Snuza mostly bc the Owlet was didn't work when she was very little so we just shoved it in a drawer lol. But now that she's not colicky it's actually really nice to see her sleep data! We got ours on clearance when BuyBuyBaby was going out of business, but if you can afford it I recommend. If not, the Snuza is quite a bit cheaper
i’ve always heard that if they’re strong enough to roll back to belly, they’re strong enough to either roll themselves onto their backs or cry for help if something happens. our little guy has only slept on his belly once and the owlet sleep sock truly gave us so much peace of mind! it’s expensive but there are cheaper alternatives!