The home advantage helps most times and Arsenal have to make good use of it if they're really serious about advancing to the finals, they'll have to score more goals at home like 2 or more, a draw won't be favourable cause it would give PSG the advantage in the returning match when they travel to Paris.
Arsenal needs to be dominant in the game, I think in the game against Real Madrid they were the underdog, but in this game against PSG, they will be the team expected to win. I hope that does not get into their head and make them loose focus. PSG remain a team with very good record this season and having eliminated some of the English teams already, they will feel some level of confidence against Arsenal. PSG have deadly attackers Arsenal needs to be weary of, it is going to be an interesting game.