Real Madrid did not get Mbappe for free; his signing bonus is higher than the amount paid for 99.9% of player transfers. But the fact that Mbappe comes to Real at the right time is 100%, first of all, because Real showed that even without Mbappe they can take all the titles, but Mbappe cannot without Real. That is, this is an ideal situation when the player is maximally interested in proving himself, because if the results with Mbappe are worse (they probably cannot be better), then many will blame him for this.
Real Madrid is the best team in La Liga and everyone knows that with full clarity. Real Madrid will do extremely better next season, always ready for the fierce competition and will do everything within their reach to ensure they're hitting upon the big winnings. Kylian Mbappe is signed by Florentino Pérez and Carlo Ancelotti, he's here to do what he does best.
His target is definitely to make a big contribution to Real Madrid, one of which is by defending the La Liga and Champions League titles. Maybe the Champions League will be Mbappe's main target, because one of the things he wants is the Champions League title, which he never got while at Paris Saint Germain.
Real Madrid did not give up on getting Mbappe, after their failure in the previous few seasons because Mbappe preferred to stay at Paris Saint Germain, this season they really succeeded in getting the signature of this young player. This completes their squad, especially in the front line which we know they really need, because in the front line there are gaps that have not been completely filled.