Hi EdenRay,
It sounds like you're referring to filtering background sounds while on a FaceTime call. If so, for help with that feature view the information below found in the article here: Use FaceTime with your iPhone or iPad - Apple Support
"Filter background sounds
When you want your voice to be heard clearly in a FaceTime call and other sounds to be blocked out, you can turn on Voice Isolation. Voice Isolation prioritizes your voice in a FaceTime call and blocks out the ambient noise.
- During a FaceTime call, open Control Center, then tap Mic Mode.
- Select Voice Isolation.
When you want your voice and all the sounds around you to be heard in a FaceTime call, you can turn on Wide Spectrum to leave ambient noises unfiltered.
- During a FaceTime call, open Control Center, then tap Mic Mode.
- Select Wide Spectrum.
Voice Isolation and Wide Spectrum are supported on these devices: iPhone XR, iPhone XS models and later, iPad (8th generation) and later, all iPad Pro 11-inch models, iPad Pro 12.9-inch (3rd generation) and later, iPad Air (3rd generation) and later, and iPad mini (5th generation) and later."
The article here also has information to assist: Change FaceTime audio settings on iPhone
Regarding the camera, view helpful information here: Change FaceTime video settings on iPhone
If you aren't able to access the features, ensure your iOS is fully updated. Update your iPhone or iPad and check your Control Center settings with the help of the guide here: Use and customize Control Center on iPhone
Reach out to Apple Support directly if the issue continues.
Contact - Official Apple Support
Contact Apple for support and service - Apple Support
Best.