Wife is abroad, no SS can I file Married Separately then Married Jointly later?

Hello,

 

I wanted to make sure if I can file Married Filling Separately then Amend later with Married Filling Jointly? My wife is currently nonresident and living abroad and no SS, we got married last year and I didn’t know I had to file form W7 to get her ITIN. I’m thinking if I should go to her place to file out W7 or is it ok to file separately for now?