First i would recommend you play some games so we know what your chess.com rating is for blitz, considering the fact that opening theory is different from rating range to rating range. Personally, I find this opening:
the easiest as I am mostly aggressive and like open positions.
However, different people have different styles. Some people like closed games, some people like open. It is all up to you and what you prefer. Play a few games with different openings and see which one you like, then stick to that one to familiarize with the lines.
I strongly recommend at least studying 4 knights game, Italian, Ruy Lopez, and Scotch.
I could use some direction. I'm kind of an unusual "beginner." I'm a late starter. I'm 58 and never really studied the game before but I like chess puzzles. My Puzzle Rating on another site is around 2,000 to 2,100. I'm not sure how that relates to a real world rating. I played my first match game last Thursday. I played white against an 1,853. When I resigned, he had less than 2 minutes left from his 90 and we were on move 29. I knew nothing at all about openings other than e4 is the most common. I proceeded with 3 basic thoughts: Open with e4, try to get control of the center, take time to think through every move. This Thursday, I will most likely play black. My question is, which defense is simplest to learn? I've been going through instructionals on The French, The King's Indian and The Scandinavian. I have limited time so I want to study what would be the safest way to make it through to midgame. My tentative plan is to study French to respond to e4 and try to get into King's Indian for anything else. Any advise? Thanks.