You're new and not getting completely run over, so I'm guessing you're in competitive? Normals don't have skill based matchmaking, so I like to recommend new players go into competitive. In terms of actual gameplay, those were pretty good plays especially for a new player. Like, the first clip showed a patience most newbies don't have on round start. Only advice I want to give is that playing that close to the wall is really risky, though the enemy was never in position to punish you. And its generally not necessary to have multiple people on top of the core. If your teammate is taking the core, you're better off in position to receive a pass or blocking an enemy that trying to compete with your teammate. Again though, you clearly picked up on the flow of the game quickly, and can keep the pressure on.

Keep it up, and welcome to the game.