All my apps seem to be open

When I reboot my phone, I expect all applications to close, similar to a Mac. However, upon booting, I notice that all recently opened, and some not so recently opened applications, are displayed in the app switcher. Is there a function similar to the Mac that allows me to set whether to reopen previous applications or not?

I’m curious about this feature, but it’s also relevant to a specific issue I’m facing. My microphone becomes active almost immediately when I turn on my phone and unlock it, and it remains on even after I applications. I suspect that an application might be opening and accessing the mic, but I can’t identify which one. Perhaps there’s a setting that keeps the mic active that can be switched off.

Any guidance or suggestions would be greatly appreciated.