I constantly have jaw pain eye pain (mainly behind or around eye) neck/throat pain and headaches.sinus closed constantly.are they related?

Can be related. : Sinus and or dental issues can cause similar findings sometimes. So it's best to see your PCP & have an HEENT examination done to see if you might need to see a specialist. Otherwise, if you can make simple changes in your diet to eliminate processed foods, sweets, sodas, caffeine, fried foods & dairy temporarily, you may notice a difference.

Likely: without an exam, I can only give general information, and sinuses connect to the other parts and inflammation of the sinuses generally gives those symptoms.