Torn ligaments in Knee

I was playing dodgeball with some friends, and when I through the ball I heard 3 to 4 pops in my knee, and then I couldn’t apply pressure to it, or rotate my foot, or extend and contract it.
I have a little more moveent now, but not sure if the poping was a critical thing.
It doesn’t hurt very much, only if I move it in curtain ways.
Is there any exercises to do to strengthen it, or anything important to do? Thank You