I have been getting a severe pain in the muscle/tendon behind my right knee, is there an exercise i can do to try to overcome this pain?

Be checked by a doctor to be sure any exercises you do aren’t making things worse.They may also recommend physical therapy,to teach you the best exercises to strengthen the muscles supporting your knee.The easiest strengthening exercise to do for this(quad-the main muscle of your upper leg)is to sit on a surface with legs bent at knee and do slow leg lifts hinging at the knee and build up reps.