My knees are in poor condition; is there any way to help?

I have knee problems, and it feels numb and tingling, and I often hear clicking sounds, so I am very worried.

I also visited orthopedics, but since I'm still young, they said it's okay and advised me to exercise diligently.

But initially, I went because I felt something was wrong, and I was frustrated.

I'm not even told what kind of exercise to do...

Is there any way if I go to another hospital?

Can it really be solved with exercise alone?

And what are some good exercises for the knees?