I am receiving messages on both my iPhone, how to stop that?

I assume you are using the same Apple ID on both devices?

• You could shut off Messages in iCloud by going to the device you do not want to receive Messages and go to Settings > [name on Top] > iCloud > Messages, and turn it off.
• You can then choose to only receive messages from the phone number instead of your Apple ID, by going to Settings > Messages > Send & Receive, and only have your phone number checked in both sections.
• You can also shut iMessage off to not receive any iMessages by going to Settings > Messages, and shut off iMessage. You will still receive SMS messages only on that device

If you have a physical SIIM, restoring the phone will have no effect on it. iPhones don't store anything on the SIM. It's just carrier information.