This is such a subjective thing that it's almost doing you a disservice to answer. If you have never played Skyrim before, I usually recommend at least a partial vanilla (no mod) play through, so you can have an idea what issues you would like to see fixed, what features you would like to see kept, and what gameplay and visual mods you would like.

Jot them down as you encounter them, and then go to the skyrim nexus and search for mods that address them.

The easiest (me = lazy) way to recommend a popular mod combo is to go again to nexus, view all the mods, and then filter by endorsements. Bearing in mind endorsements don't mean there are no bugs or that the mod is as great as it is made to sound, it does help establish the long-standing and popular mods. Once you narrow down your list of candidates, take a look through the bug and comment sections, to see what problem patterns there are and of course read the descriptions to help avoid conflicts with other popular mods.

only thing i consider must have is the "no killmoves" mod from nexus

Ah, I'm just the opposite. I installed Violens, so I could have ALL the killmoves.

USLEEP - if you have all 3 DLCs or Skyrim LE.

(I wish people would stop with this pro-Nexus thing. The best place to get USLEEP is from the author's web site not Nexus).

Your set up will run pretty much any mod. Add them one at a time after reading the mod page including the post section to check for possible bugs. Get a mod Manager like Vortex from Nexus mods and learn to use it. Gophervids on Youtube has tutorials to get you started. There are thousands of them on Nexusmods.com and it has a free service as well as memberships. Check the game you are using (Skyrim or Skyrim SE) They are not the same as one is 32 bit and the other 64 and the mods are not interchangeble for the most part.