how can i text with different number on my cell!
You cannot fake your own cell phone number when sending a text message, if that’s what you’re asking. The number is tied to your SIM-card.
This is a good thing BTW; consider what would happen if someone else could send a threatening or insulting text message to someone, but with your phone number as the apparent sender. That would be big trouble for you.
If you meant something else, then please elaborate.
Welcome to the forum.
A jailbroken iPhone can use Google Voice to send texts and it will show as coming from your Google Voice # and not your cell #.