can I connect beats wireless headphones to my apple watch

Absolutely.

Good chance they may already be configured to work with your Apple Watch if your headphones are configured with your Apple ID. But pretty much any bluetooth headphones can be paired with your Apple Watch.

I have paired 4 different Bluetooth headphones (just to see if I could) to my Apple Watch.

• AirPods (the easiest)
• Sony Noise Canceling Headphones
• and 2 different 15 year old Bluetooth headphones

The hardest part for the non-AirPod headphones, was finding the instructions that put the headphones into Bluetooth "Discovery" Mode. Especially the 15 year old headphones. Good thing I could read the model numbers from the units and Google for the information.