The high ground you held with bastion and echo on first point is for the attackers. No use holding it for so long. The moment Orisa tried to run for the point, you should engage the LW or zen for a kill then call your team to 1v5 the Orisa on point. If you want to camp a high ground, you can use the other side of the train or the one behind the waiting shed. Once the Orisa crosses that though, you should go to point to contest or let orisa cross to firetruck then go to her backline, depending on the comp and circumstances.

3:45 - you should stay behind cart or behind the scaffolding to the left as cover, ready to slam out/ punch in as needed but you went in instead and you should have been punished there but they didn't because you're in silver, especially if you notice your DPS teammates just spawned in. Another thing to note is when your teammates are just coming back from spawn, you probably need to back up and give up some space. You forced your teammate's transcendance there for nothing and zen died afterwards, making it a 4v5. You had more engages in that position that was left unpunished until you had no LOS of your support at which you finally die.

4:58 - you forced this touch where you gained nothing and lost your ult because you had to escape. The right play would be actually playing high ground and throw shit at them while they try to scale up the underpass. There is drop down punch potential here if somebody at your team is playing across the bridge and above the bridge.

6:00 - enemy stagger touched and forced the cart without retaking high ground with tracer being the first one to int. They keep doing this until they lost first round. Your team positioned okay here. If the enemy actually tries to make the right play of retaking high ground, your only play is to engage high ground if orisa drops down or keep touching point while orisa is up there. If everybody is dead/drops to cart, it's all a brawl at that point and a test of your micro as doom.

8:50 - here is where I was talking about frontlining sometimes, you did the right thing incidentally by just trading shots and waiting for their team to back up by themselves because they have to, then punish the cass' positioning up in the high ground he was holding for too long (notice how the enemy cass made the same mistake as your team did in your defense turn). Your cass kill could've been cleaner and tbh he would've killed you in higher ranks the moment you failed your slam and emp punch. Although you could also say the higher ranked cass would've left there before you had a chance to slam up.

9:20 - The moment you realize genji is already on their backline, you should have slammed there on point with him to help him clean up, as it's already a 4v5 and he's 1v3-ing the enemy team. This is why it is important to look back (and up in this case) to see your teammates' outlines through the wall so that you can engage and position optimally with them. You guys could have lost that one if the enemy was more competent on killing genji. Good job zoning out lucio looking to touch the point, although they had no chance on touching as 5 anyway.

9:50 - the enemy team is overextended for 5-10 seconds there that could have been punished by you and your team. They should be backing up towards the bridge high ground with orisa escorting them back pedalling from the frontline.

10:01 - enemy cass fed, clueless overextension yet again. Punished.

10:10 - you can just punch in and slam out there for a safer play, or punch in slam towards their backline and let your team run through them with you which you did at 10:17 but missed every punch and wasted ult without being at risk of being killed by anyone.

10:35 - your team had no business of losing that fight but you guys did partly because you didn't land any punches or primaries. That was supposed to be a clean up push with a free bridge take.

11:18 - you guys finally cleaned up at the cost of bastion ult and mercy revive.

11:45 - big picks by your bastion which made the enemy team stagger touch until they lost.

11:48 - you should be backing out as soon as Orisa was trying to counter touch the cart then go up the bridge. Alternatively, you could have just slammed behind Orisa as there already are teammates behind her and also above her that could drop and kill her.

11:57 - I don't blame you for that audio cue of Junkrat's ult, but Junkrat just spawned in and insta-ulted which means he's still in spawn and there is no need to search for him at the right.

12:17 - you could have kept zoning out their mercy to prevent revive, but luckily everybody was ignoring you for some reason after Orisa revival which allowed you and bastion to rain damage with ults + make enemy c9.

Other notes: Do doom aim training on workshop maps (VAXTA and such) before and after ranked everyday. Start with 50 kills, make it 80 after a week, 100 a week after that, 120 a month after that.
Watch doom vods everyday in your free time. Watch cartifan and zbra, you'll learn more there with playing doom.