How to turn off sounds for everything except alarm

Solution 1:

This is answered by @Tetsujin

Alarms work even on silent mode.

My iPhone has been on silent mode ever-since I had it. You can manage the alarm sound level for the alarm you create while selecting the alarm sound. Tap Edit on the alarm entry --> tap Sound --> Choose the sound and immediately increase the volume using volume buttons.

Just keep the Silent Mode on by sliding down the physical Silent Mode switch. Your music will play at the volume level you want. No screenshot/camera/notification sounds will ever come out. Don't Disturb would be a different outcome.