Hello and welcome to Apple Support Communities, Sophie1106.
If I understand your post correctly, you'd like to be able to silence your iPhone without powering it off altogether. I certainly understand wanting to receive notifications without distrubing others. I'd like to help.
Make sure you're using these steps to silence your iPhone:
The Ring/Silent switch is on the left side of your iPhone. You can use it to control which sounds play through your iPhone speaker.
Put your iPhone in Ring/Silent mode
When your iPhone is set to ring, ringtones, alerts, and sounds play through your iPhone speakers.
When your iPhone is set to silent, you won't hear ringtones or alerts, but other sounds will play through your iPhone speakers and your iPhone will vibrate.
These settings affect only your iPhone speaker. If you use a headset, sounds play through your headset, even if your iPhone is on silent.
To put your iPhone in Ring mode, move the switch so that orange isn't showing.
To put your iPhone in Silent mode, move the switch so that orange is showing.
See the full article here:
How to put your iPhone on vibrate, ring, or silent mode
Let us know if that resolves this issue for you.
Thanks for using the Apple Support Communities. Take care.