It's a good thing that Mbappe is been signed by Real Madrid for five contracts but my area of concentration is where would Ancelotti choose to play Mbappe fully as his wing since Ancelotti likes playing 4-4-2 or 4-3-1-2 formation for Real matches. Let's not forget that there are quality players like Rodrigo, Vinicius, and Bellingham occupying such playing formations at the frontline.
I think that by next season, Ancelotti will introduce another tactical formation of 4-3-3, to bring Mbappe in, in every Real Madrid match of Laliga or Champions League, to avoid issues or confusion that will arise based on how to feature Real Madrid frontline players
The five-year deal is perfect for Mbappe so that he can stay with the team for a long , and Ancelotti should also add a release clause of a huge amount in his deal so that he will not have a chance to leave the team before his contract expires.
Ancelotti will have to use Mbappe by all means because the team needs him in the squad, and since they don't have any reliable strikers and they equally don't have any intention to sign any soon, he will have to use them all in the front line.
Vinicious, Rodrygo, and Mbappe will be switching positions in Madrid's front line for an effective result, he can use any formation for them since Mbappe can also play as a forced 9.
Mabppe individual qualities make it easy for Ancelotti to place him in any position, Ancelotti can even pair Vinicius, Mbappe and Rodrydo in one lineup. I think Ancelotti can accommodate all the players in his squad, everyone can get playing minutes according to the quality they have, because Real Madrid is taking part in 7 competitions next season. Apart from the formation that Ancelotti will use, it all also depends on who the opponent they will face. Apart from that, Ancelotti will of course carry out various experiments as usual, with the experience he has, I don't think it will be difficult for him. Florentino Perez can really protect the club interests in the long term, the five year contract duration given to Mbappe can make management calm without being busy with various rumors in the future.