General treatment that would be advised given your age and symptoms is avoid cross legged sitting, no squatting. Knee and lower back muscle strengtening exercises.
Next Steps
in case of partial or no relief or if you have to take pain killers on daily basis please get x ray knee done and consult your orthopaedic surgeon, it's most probably arthritis. back also suffers arthritis that may one of the causes of the backache. a proper diagnosis will help in making a definite plan of action. only personal appointment on examination will help.