What to expect when getting my hair braided with weave added in for the first time?

The reason why I am asking this question is because in about a week I will be getting my hair braided into cornrows with weave added in for the first time and I'm feeling a little nervous as I dont know what to expect. The brand of hair that my friend will be using is called kanekalon I've never heard of this brand before and so I've watched a few youtube videos on it and I thought the hair itself looked really nice and most people in the videos seem to like it which brings me to my first question Is kanekalon hair one of the best brands of hair to use for hair braiding and how much does it typically cost? I dont want super long braids ideally, I would like for them to be slightly past shoulder length. Will 1-2 packs of hair be enough? How long do the braids typically last? My friend told me about two weeks but I was hoping they would last me about 3-4 weeks. Will leaving the weave in for 3-4 weeks cause damage to my natural hair or cause it to fall out? tIs getting one's hair braided with weave added in much more low maintenance than using just one's own hair? The reason why I am asking this question is because I am african american and my hair is both natural and super thick and so I'm hoping that the braids will put an end to all the fuss that I have with styling my hair in the morning. How much hair growth can one expect to have with braids and weave added in? Your help is greatly appreciated!