AirPods, particularly the newer versions, use a version of Bluetooth that is not natively supported by Windows 7.
You should be able to buy a Bluetooth adapter that will work with your AirPods.
To check, do the following:
- Determine what version of Bluetooth your AirPods require. For example, AirPods 4 use Bluetooth 5.3 (see https://www.apple.com/airpods-4/specs/)
- Open Device Manager on your computer (click Start, type Device Manager in the Search box, and press Enter)
Double-click the Bluetooth category to expand it
Right-click your Bluetooth adapter (receiver, transceiver, etc.) and select Properties
Select the "Advanced" tab
Check the LMP version
- LMP 0.x - Bluetooth 1.0b
- LMP 1.x - Bluetooth 1.1
- LMP 2.x - Bluetooth 1.2
- LMP 3.x - Bluetooth 2.0 + EDR
- LMP 4.x - Bluetooth 2.1 + EDR
- LMP 5.x - Bluetooth 3.0 + HS
- LMP 6.x - Bluetooth 4.0
- LMP 7.x - Bluetooth 4.1
- LMP 8.x - Bluetooth 4.2
- LMP 9.x - Bluetooth 5.0
- LMP 10.x - Bluetooth 5.1
- LMP 11.x - Bluetooth 5.2
- LMP 12.x - Bluetooth 5.3
- LMP 13.x - Bluetooth 5.4
Thus, if you have AirPods 4, then unless your LMP version shows as 12 or higher, you would need to buy a Bluetooth adapter that supports Bluetooth 5.3.
Beware --not all of the newer Bluetooth adapters will have a Windows 7 driver; be sure to check before you buy.