India should offer axxenation plan like kashmir to them
Nah, wouldn't be too practical. They're far away, without proper geographic contiguity, and are pretty distinct + clearly want freedom. What India should do is put everything behind them to become independent, help the Pashtuns of the NW Pakistani "Frontier" region merge back with Afghanistan, try and foment separatism in Sindh & the Southern "Saraiki" part of Pakistani Punjab (and help them become independent countries as well).
The portion that Pakistan calls "AJK" should be left alone except for select, key infiltration routes (eg Haji Pir Pass) & dominating features + Sharda Peeth. That portion is now super radical and has had its demography changed massively by Pak Punjabis. Find a way to merge Gilgit-Baltistan; the connectivity to AFG/Central Asia and completely breaking Pak-Chinese link up are worth their weight in gold. Would also be smart to get a proper foothold in Indian J&K and recaptured G-B with proper demographic rebalancing through West Bank style settler model.
From West Punjab take key features like Akhnoor Dagger, Shakargarh Bulge and key religious sites close to the border like Kartarpur Sahib. From Sindh take the high Hindu population % districts in the East.
Let the remainder of West Punjab + "AJK" be a rump "Pakistan" which is disarmed, denuclearized and essentially defanged + landlocked and at India's mercy permanently.
Turn all the successor states into treaty bound protectorates and keep them firmly in the Indian grip/influence. Find a way to at least de facto (if not completely) merge Nepal, Bhutan and Sri Lanka (there's not much of a reason for any of them to be separate nations, all it does is divide Dharmic peoples and give China various footholds around India).
And finally, some day sort out Bangladesh and take the Rangpur, Rajshahi and (most of) Chittagong Divisions - which have significant Hindu and Buddhist Chakma populations respectively. This would strengthen the Siliguri Corridor and also grant sea access to the Far Northeast.
This would be a "complete" India - and should've been achieved in '47 and immediate post-Independence period under competent leadership.