How update my iPhone x without wifi or computer ?

You have to update either over WiFi or through your computer. Your choice.

Go somewhere that offers free Wi-Fi.

Hi there Doddy2,

I’m happy to see that you posted to the Apple Support Communities for assistance and I understand you’re wanting to know about updating iOS wirelessly. I can help. 

You’ll find info about all of the available methods of updating wirelessly in the the section “Update your device wirelessly” here: Update your iPhone, iPad, or iPod touch

Take care.