When I was born 30 years ago my mom was told by her dr. to put me to sleep on my tummy.
10 & 15 years later she was told to put my siblings to sleep on their sides using a wedge.
2 years ago I was told to put my kid to bed on his back.
We all survived. Do what you feel is best.
My baby was like that at first and I started swaddling her and she has been sleeping through the entire night for the last month she will be 3 months on the 28th
My 3 kids slept on their tummies from birth.
My daughter from day one would roll over to her side or stomach soon as we lay her down. We were told as long as we lay her on her back that it was fine. I just check on her through the night.
Both my babies slept on their belly from the time we came home from the hospital 
they are 4 & 2 and still sleep on their stomach lol
My son slept on his stomach when he was first born he refused to sleep on his back too. So let’s just say I didn’t get much sleep I was afraid he would stop breathing or something so I just kept waking up constantly to check on him and he was just fine. I also breastfeed my son so most of the time he slept with me.
Check his neck range. One of mine had a dislocated shoulder from birth and would only not hurt on her tummy. It took awhile to figure it out.
All my babies slept on their tummies
My little slept on his belly fine
My son would only sleep on his side. I had these two props that had material attached and Velcro to adjust. Im not sure what it was called but it helped a lot