What is the best opening to start with?


As white I like the King's Gambit or Queen's Gambit. Both seem to be on the easier side to learn. As black I usually play King's pawn or Queen's pawn.

DO NOT STUDY OPENINGS as a beginner!
Endgames, Tactics, Strategy, and only after you have MASTERED (not just spent an hour, see you in 2 years) all 3 do you worry about openings.
Until then, it is opening concepts. Control the center, don't move pieces multiple times unless threatened, castle and get the king safety.
After 2 years, chances are, you probably are playing an opening and don't even know it as you proceed to learn which patterns you best understand. I was playing the French before I knew what the French was. It wasn't 15 moves deep, but that is what told me to be a French player for 29 years.
Forget about openings for now.

As white I like the King's Gambit or Queen's Gambit. Both seem to be on the easier side to learn. As black I usually play King's pawn or Queen's pawn.
What YOU LIKE and what the OP NEEDS TO DO are TWO TOTALLY DIFFERENT THINGS!
See post 4. If I were to just spout what I played for 29 years, I could tell him the French because that was what worked for me, but what works for you or me does not work for everybody!
Hence the approach mentioned in post 4 being what he needs to do, not just listen to people spew random openings. Soon some dumb clown will have him playing the bong cloud or whatever this dumb Cow opening is we hear about.

As a beginner, the most simple openings are not always the best. Kings gambit opens up your king (Queens gambit is better), Caro-Kann clamps your pieces, etc. You need to play openings that best suit you. Learn your playstyle, then main an opening that complements it. Like if you're a defensive player, then Gambits probably aren't for you. I like focusing on big attacks on my opponent's pieces, so I main Italian. Also, learn openings for BOTH colors. You sometimes may think you can get around this, but trust me, a different color almost always means a different strategy, especially in the opening.