Everyone learns at their own speed. Some drive Lamborginis and some ride the short bus. Some instructors are more knowlegable than others. Itll take u as long as it takes
You will need a lot of time. Trust me im in Kung Fu San Soo just one of the many styles of Kung Fu. It takes a while but you can do it with time effort determination and dedication.
Kung Fu is one of the harder martial arts to learn but how long you need to learn it is entirely up to you. How good do you want to be? The better the more time you have to spend in the art. About getting kicked, you don't have to spar if you are afraid of getting hit.