Hello Kayla Yin,
Welcome to Microsoft Community.
After I have fully read the question you posted here, can I presume that this old Surface device is not with you at this time?
In fact, all you have to do for now is simply pair your Bluetooth keyboard with your new Surface.
If you still have your old Surface and it's still in power-on condition, you can disconnect pairing in Bluetooth & Device anywhere.
I'm assuming that maybe you're using the following devices:
So now what you need to do is:
- Press and hold the pair button on the bottom of the keyboard for 5 seconds, until the LED starts to flash.
- On your Windows 11 PC, select Connect if a notification appears for your keyboard, then wait for it to get set up.
Here is the link to support that may be relevant:
Use Microsoft Bluetooth Keyboard - Microsoft Support
However, if you are currently experiencing some problems when trying to pair Bluetooth devices, please refer to the following Bluetooth troubleshooting:
Pair a Bluetooth device in Windows - Microsoft Support
Fix Bluetooth problems in Windows - Microsoft Support
If anything is unclear, please do not hesitate to let me know.
Best Regards,
Mitchell | Microsoft Community Support Specialist