can anyone give me some tips about my jumping technique when trying to dunk?
I feel like my approach/ jumping isn’t right in the first place and I can get higher
5’'9 and the rim seems to be around 10 ft ~
try to get a tight palm on the ball, people will reduce the arm swing in their jump when trying to dunk if they can’t palm the ball.
You have a shallow dip, people with shallow dips tend to go better off one foot.
Actually jumping of 1 leg is very hard for me, I can’t even touch the rim
2 legs I can hang easly
Just because somethings easier doesnt mean its better, of course two legs is easier at the start. Have you even practiced much jumping off of one leg?
Actually no 
Can you please explain why jumping of 1 leg is “better” for me? what is shallow dip exaclly?
I wasnt saying its better/ its not “better”, some people just jump more proficiently off of one leg than two or vice versa. If you havent practised much with one leg than how can you know if it doesnt improve your jumping or not?
http://jump-science.com/force-vs-technique-knee-bend/
Read this article and that should help.
Imho being good with both ( jumping off of one leg or two) is better than only being good at one or the other.
Example:
“One-foot jumping is good for taking off without any pause.”
“Or two foot jumping is good for the times where you need to time an alley-oop etc.”
So in addition to more explosive training ill try adding 1 leg jumping technique
thank you for the wisdom !
Looks good, but you should try to ‘step in’ violently into your last couple steps. What you have going on in a ‘hop in’ which doesn’t help you transition horizontal force to vertical force. Make sense?