Dunking

Realistically , will i be able to dunk if i can grab the rim with two hands off one step?
If so, how close am i to dunking?

To dunk you'll need to get one hand at least 9 inches above the rim. So you are close.

I agree it appears you are close. A couple of things that can help, get a tennis ball and try dunking that. Also, a volleyball or soccer ball with some air let out of it.

Working on some hand and fingertip strength can also help. Look up some vids on strengthening your grip to palm the ball on YouTube.