What number should I enter before sending a text message to my cell phone in Los Angeles?

First of all, I understand that the international prefix of China is 00 or+,and the country code of China is 86.

If you are in China,

Then there is China international prefix+the country code of the other party's mobile phone+the other party's mobile phone number.

Add 00 1 before the phone number, that is, 00 1+ mobile phone number.

00 1+area code+calling phone number

The sending message can be sent directly. You can send a message by transcribing the other party's number, which must be all numbers (country code+area code+mobile phone number). If you make a phone call, you need to handle international long-distance service, and you can make international long-distance calls after opening.