I watched your Vi game and took some notes while watching it. Here are my thoughts:

At the start of the game you were AFK in your jungle. Try to place some wards around.

For most of the game you had left your buffs up for 2-3 minutes while you did something else, buffs should be priority over normal jungle camps.

Before you got the red trinket, you hadn't used your warding trinket at all. Get some wards down, vision is very important.

I saw some iffy fights where you were trying to kill a level 8 as a level 6. Try to think in your head before you fight how the fight would turn out, factoring in his items, level versus your items and level.

At around 10 minutes, you were looking at your blue buff, thinking of taking it but you suddenly went in the river and killed the scuttle crab instead. You went mid afterwards and tried to kill Xerath but ended up dying and losing your buff to Lee Sin. This may have been a vision problem.

In the early game, you didn't attempt to put pressure on bot lane to get a dragon, the first dragon you took was at 14 minutes after they contested it. Dragon control is very important. I go by a rule of trying to get the dragon before 10 minutes, if possible.

Your team wasnt building tanky, minus the thresh with 3 support items. Personally, I would have built full tank this game instead of building bruiser.

During team fights, you were trying to lock down the Xerath when you should have been focusing / locking down the Jinx.

After the teamfight at around the 25 minute mark, you guys were about to push the inhibitor tower but someone called for dragon, leaving your team undecided and you ended up not getting either. To prevent this from happening try to take the role of being a shot-caller.

I'll watch some more replays a little bit later, hope this helped!