Will this pc do for gaming and editing?

Try and get a gtx970 or R9 390 they will last longer.

Don't get the B1 PSU, get the B2 or better. Newegg always has good rebates on good units. Check the PSU Tier list in the Components section and get a Teir 1 or 2.

Other than that looks great.
 


Those parts aren't in my budget
 


Sorry, just noticed you are in UK. Video editing? The 4690k is the best you can do for budgetary reasons.
 
Honestly any 4th gen i7 will do of course the more you pay the faster you can render your video's but that's your choice.
 

I'm actually in the US