Moksha vs Kaivalya vs Nirvana vs salvation details below
Moksha is a Sanskrit word, that means liberation from the cycle of births and re-births.
Nirvana is a Sanskrit word, more used in Buddhism, means the end of all suffering and dissolves into cosmic consciousness or emptiness.
Moksha and Nirvana are synonymous, the end of the cycle of births and re-births means the end of suffering hence Nirvana.
Kaivalya from the word kevala in Sanskrit means liberation from everything and remaining alone with not connected to anything, thus not impacted by samsara.
Salvation is the term with respect to Abrahamic religions, eventual entrance to paradise, and redemption from sin.