When you realize you've lost your phone, the first thing you should do is contact it from a different number. Try dialing your number right away.
you can remotely lock your iPhone. By logging into another device, you can turn on the iPhone's Lost Mode.
If calling does not help, try to locate the phone using your phone’s GPS.
You can delete all of your data from your Google or iCloud accounts, but you won't be able to trace your device again after doing so.
If you believe you have not misplaced my phone, and ideally that it was stolen, then call the police as soon as you can.
Ask your service provider to suspend your SIM card as soon as you notice that your phone is not receiving any calls from you.
Including Google and other email accounts, update the passwords for all of your accounts.
You can manually unlink all of your cloud accounts if changing your passwords does not satisfy you mentally. disassociating your cloud storage from services like Dropbox, Google Drive, etc.