flexibility

I noticed i have 3 tight muscle, but i don’t understad what muscle.
when i try to stay in squat position i must stay whit my head over my feet.
i have another tigh muscle, only in the right leg, when i lean on my back and try to put the right leg on my chest, i feel pain in the union of leg whit abd and in the abdomen.
the 3 is when i lean on my abdomen and flex my leg, i notice a pain in the harmstring region.

what’s the tigh muscle? what stretching i must do? this can influence my run?

Are you stretching after a warm up?

yes.
normally i do
run 6-8 min (low intensity).
dinamic stretch
drill
static stretch
med ball circuit (1)
then i start.
but i have this 3 problems (in the other part a normal flexibility)