Ask for what I need
One way to say it.
Use these words, adapt them, or choose something else.

I am going to lie down over here with my headphones for a bit. Still here, just quiet.
Before you use it
Think about what you need and who you are speaking with. You can say the line, write it or show it. The other person may respond in different ways.
A sleepover · Ask for a break
Availability depends on Apple approval and your region.