Can I use my sims card that I use now in my iPhone too my IPhone 12 pro

Yep. Switching the SIM card is common when transferring phones and both devices use the same Nano-SIM card. Sometimes the tray is a little difficult to remove, but can be done with a small paperclip.

Remove or switch the SIM card in your iPhone - Apple Support

The answer is yes.

You can use the same card Nano-SIM for all iPhone models since 5. Below you have full compatibility list:

Learn which size SIM card your iPhone or iPad uses