Well, the reality is the Indian nationalist movement was
The question isn't about what happened and failed in the otl, if this atl happened would it lead to a independent India/multiple Indias and if so would this lead to The British empire to either exit ww1 or collapse. Or would the British crush the rebellion.
Well, the reality is the Indian nationalist movement was very fragmented (Hindu, Moslem, Sikh) and not particularly strong, as witness their failures historically.
As it was, even when a large part of the Bengal Army mutinied in 1856, significant elements remained loyal, as did almost all the troops of the Bombay and Madras armies...
It's a fair bet it would have taken the stresses of both world wars to both weaken the British hand in India and strengthen that of the nationalists; to expect something similar in 1914-18, given the historical record, requires some real changes in British policy toward India, and Indian "unity" in India, in the Nineteenth Century.
If a major rebellion did occur, it's a safe bet the British, their Indian allies, and - quite possibly - with assistance from the Anzacs and French and Portuguese, both of which retained colonies in South Asia at this point, and possibly even the Japanese - could have defeated any reasonably realistic rebellion, albeit at significant cost.
Given the above - large but failed rebellion in India in 1915-16, for example - one would expect the theaters where Indian troops were deployed in large numbers historically (Mesopotamia, Palestine, etc.) would presumably have remained areas where the Allied offensives were delayed or simply never begun until later in the war... so the Turks gain an advantage (which is what the Germans and Turks were hoping for, obviously, when they backed the historical efforts).
Odds are still certainly in favor of the Entente winning the war, especially after 1917 and the US entry, but the combination of the Russian collapse, a stalemate in Southwest Asia between the Turks and the Allies, and a need for substantial garrison forces in India in the aftermath, means the war may last until 1919, at which point the AEF is in a position to invade Germany with Allied support (so, massed armored/motorized formations, airborne operations, etc. two decades earlier than historically).
The Ottoman Empire presumably still breaks up, but the Arabs may actually manage to avoid the Mandate system in what became Palestine/Lebanon/Jordan/Syria/Iraq, which causes some major ripples across the rest of the Twentieth Century.
As far as India goes, the British may in fact hang on with even more force than they did historically, but by the beginning of the 1940s, the writing presumably is on the wall; if there is a second war, the Indians are going to demand Dominion status at least, and the British would presumably be hard-pressed to say no...
Lots if ripples, obviously.
Best,