Best place in Turkey to move to for young single expat?

Hi everyone! So I'm a young, single dude planning on moving to Turkey very soon, but I am trying to figure out which city would be best to meet and mingle with other young people, join the community (both local and expat alike). Just to preface, I won't be needing to get a job in Turkey, but am potentially looking to buy a small apartment.

Though I generally like the coast very much, am I right to assume that places like Antalya, Bodrum, and Fethiye attract mostly the older crowd (established families, retirees, and the like) or is this not the case?

I've also looked heavily at Izmir as well, which looks awesome but as I don't know much Turkish (yet!), am not sure if  that would be an issue if living there vs. a more international city like Istanbul (which I love, and am also open to)?

Anyways, thanks for your time in advance - any advice would be greatly appreciated on this!