It is not the case of the referee alone when you want to determine the outcome of a game, the referee can be an obstacle for a team to successfully win their match but if the players are determined to tackle their opponents by playing and focusing on scoring, they can finally get a good outcome that will lead to their winning.
It is not every game in football that the referee can have a major influence on, because there are some games that the referee might easily decide the fate of each teams, especially if the teams are of equal strength or they are close to, but if a particular side is way stronger than the other team, just know that the referee may be powerless in influencing the game into the favor of the weaker team.
Sometimes the referee might issued a red card to a stronger team, just to make things difficult for them, but if they are strong enough, they can still win even with a man down, even though it's not an easy task to carry out.