How to Play the Saxophone
The basic position
Supported by the right thumb, upper teeth, and strap
The saxophone is held in three places when played. The lower lip covers the lower teeth.

Find a playing posture that suits you
The most fundamental part of your posture for playing the saxophone is finding one that makes it easy for you to play. As long as you don't feel any pain anywhere, even if your neck is bent while playing, you shouldn't have any problems. The angle and position of the instrument will change based on the shape of your mouth when playing and the alignment of your teeth, so try different things out find the posture that feels the most natural to you.