Marriage in groom home country

Asking on behalf of a friend. He is from india and his partner is from EU. both are in a relationship and living in uk. They got married back in india in April 2020. Boy is an international student. Question is is their marriage acceptable in uk? Their marriage is validated, legalised and formalised by the govt of india. Can the boy apply for EU settlement scheme on the basis of this marriage document? As his partner has the settlement status. Thanks