The i7 is $100 more according to partpickers lowest price, not worth it, the i5 I suggested will perform fine, and is more than enough for gaming and video editing.
He didn't mention how much video editing he would be doing, so I assumed not a lot, but if he thinks he needs more ram then the mobo I suggested has 4 slots so he can upgrade to 16gb, he's never going to be using more than 16gb unless he's doing massive amounts of really high quality video editing with a lot of other programs running.
SSD is included in my build, one of the best you can get for price.
Anyway, Godto, you make very little sense, use punctuation, and the letter "s", and what do you mean: "also the newer game like watchdog use lot of core"
Watch dogs is very poorly optimised and is a straight console port, do not base your PC build off of the requirements for another terribly optimised game from Ubisoft.