You should learn the common rules of football - a win is always 3 points, and points do always matter first

The goal difference only comes into play if you have the same amount of points, then the team with the better goal difference will get the superior rank.

If you win today, you will be 4th at the end, no matter what the results of other teams are.

If you lose or draw today, it depends - if the 5thplaced team wins, you will end up 5th, if it draws or loses, you end up 4th.