New wallet upgrade

I have a Trezor wallet and recently got a safe 7. I want to activate this wallet and put my stuff on it but I’m a little freaked out!

Do you just fire it up with the trezor app on Desk top, put in another new PIN and then your seed and then it transfers over to that wallet as well? Does my old wallet stay “active” as well?

Thanks for any tips - won’t be answering DM’s