Kegel?

Ok so I’ve read the instructions and read plenty of posts on kegeling but i just cant find my answer. Ok so your all saying that kegeling is the flexing of the BC muscle. That is all?

It can be done erect or flaccid? Without having to apply pressure to it directly with my hands at all? So i can be sitting on a bus, hands out of pants, gazing out the window not looking sus at all and at the same time be doing PE exersizes to improve my erections?

Yes, you know the muscle you use if you were going to pinch off a piss midway, or to hold a piss in, thats essentially a kegel.