Muslims living in non muslim country

Assalamualaikum,I reside in India where till now we Muslims r easily performing our faraiz accept unwillingly we had to be involved in interest,eg I work in medical college where they transfer salary in our salary account which after some time they give interest which I donate without intention of sawab,my question is is it necessary for muslims especially for indian to migrate to muslim country, please explain the verses 97-100 of ch 4 of Quran, moreover it is difficult to migrate because these countries may expel us under some new law eg Kuwait is sending 8 lac indians back to india, moreover all so called islamic countries r not completely islamic eg they serve pork, alcohol,they r also involved in riba so no country is 100% islamic and Allah in ch 2 v 208 of Quran says come in Islam fully and m I be a sinner if I get interest on my salary because in india there r no Islamic banks, please clear my query.Allah fiz