Transmission

There is not much I can suggest to you based on the limited detail and information you supplied. But A non working transmission is not something a regular home mechanic can usually repair. You will need to have it towed to a mechanic or transmission shop for a proper diagnosis and repair. The 2002 S60's had weak transmission to begin with and unless the car is great shape otherwise you might want to think about scrapping it vs putting a few thousand into it.

It's probably shot... your S80 T6 has the GM 4T65 transmission, which is notoriously weak and prone to failure. Then again, you have to be more specific, because it could be a simple issue like a shifter button or microswitch if the shifter isn't moving. However if the car isn't moving while in gear, rule out the simple stuff first (broken axle) and then check for codes with VIDA or another scan tool that can view Volvo proprietary codes. Worst case, it needs to be rebuilt or replaced.