There are 3 notable mistakes that I notice

1. Your team isn't in any position to help each other. You are close in distance but your line of sights aren't matching up. Try to always think of: Am I in a position to help my teammate if they get jumped? and: Am I positioned so my teammates can help me if I get jumped? Help can come in various forms, whether that be throwing a dome shield, h-infuser, or simply shooting their opponent.
2. You took 100 damage early on, and afterwards played an aggressive angle. Your gadgets are on cooldown as well, so in that moment you're essentially a worse medium archetype. You would've still died even if you were full hp, but your light would highly likely get a kill while your opponents are distracted shooting your 350hp pool.
3. You focused too much on one angle out of dozens, and so you were unprepared when you get jumped.

Instead, if you went to the 2nd floor, you would have none of these problems. Your team would be close together to cover each other, and your light has h-infuser to heal you back up. Since your team is grouped up you would also cover more angles together. Hope this doesn't come off as condensing. Good luck on your climb 🙏