Being that Blade Runner 2049 is coming out at the end of the year, I'd recommend the orginal Blade Runner.
Ex Machina.
Metropolis. One of the first Sci Fi movies ever made. It's old but really cool. What they went through to piece together the movie is a very amazing story. If interested read up on its story before watching the movie.
Ghost in the Machine. I know they are filming the movie with Scarlett Johansson right now, but the original is still awesome.
Forbidden Planet is an oldy but Goody
Edge of Tomorrow was pretty good
10 Cloverfield had some great twists and story to it
ohh yes! Love it!
https://en.wikipedia.org/wiki/Dark_Star_(film)
Be prepared to laugh as well as be otherwise entertained.
hmm Inner Space and Not Of This Earth.
Not a movie but I would totally recommend watching Doctor Who!
https://en.wikipedia.org/wiki/Doctor_Who
You can watch it for a very long time as it aired in the 60ies if I'm not wrong!
My Favorite Science Fiction Movie Is Avengers Infinity Wars.And I Think Its The Best Movie To Watch.