Click on your profile picture at the top of the page-> go to settings-> then click on your Security & Privacy-> phone verification, and follow the instructions.
And when your account is verified, the blue check mark will appear and you have done it correctly
Go to settings, click on "Password and security" then "email option" click on your email it will give password and ask to verify. Then you will get notification on your email to verify.
Click on your profile picture at the top of the page-> go to settings-> then click on your Security & Privacy-> phone verification, and follow the instructions.
And when your account is verified, the blue check mark will appear and you have done it correctly