Even if you think a draw is a fair result for the match but I think one of the two teams deserved to win the match. Manchester United played very well, while Barcelona also had it. Both teams appear to attack making these two teams score goals alternately.
Barcelona had a good chance in the last few minutes of the game, but they had to miss because the ball hit the post. Obviously a draw isn't the best hope of Barcelona or Manchester United, but either way it's good enough for both. In the second leg, I expect a match with the same atmosphere between Manchester United and Barcelona. Both teams have the same chance to qualify, but we just don't know who will step there.
For second leg Barcelona potential losing both their crucial players between Gavi have confirmed with yellow card accumulation and latest news about Pedri have absent several weeks later after injuring. Talking about potential team have chance to qualify next round seems Manchester United with advantage playing at home is more favorite than Barcelona.
I think draw is crucial result for up coming second leg and both team between Barcelona or Manchester United have the same chance qualify to next round, there are not important for Manchester United with away goals and next draw on second leg will have taking trough penalty kick for the winner.