What would the Ottoman Empire look like if the central powers had won WW1. With its territory reclaimed would it be able to stave off its defeat, or still collapse just as it did in OTL?
We've actually covered this in enormous detail in multiple past threads if you do a search.
It the CP won, how would the Ottomans be staving off defeat? By definition they have won.
The situation for the empire would depend upon when the victory occurred. If it's early, the Ottomans will end up with their territory in 1914, and will also probably get the Dodecanese back.
If it's later in the war, they will need to reestablish their authority in areas occupied or in rebellion, but these are very minor - the area around Basra, and the Hijaz. If Russia collapses, the Ottomans will gain probably gain Caucasian territory.
Under no conceivable circumstance will the empire collapse. People sat around for centuries waiting for the empire to collapse, but it never did, and had to have territory violently wrested from it. And it didn't "collapse" in OTL - politically and militarily it remained on its feat without interruption, although it did become a Republic - and that was largely because the British violated the Armistice and occupied Istanbul. In a victorious scenario, that won't happen.