English Grammar A1 Level: A modal verb is a type of auxiliary (helping) verb  that has no meaning on its own but it modifies the main verb, changes  its meaning and gives more details about the action.

The verb would is a modal verb used to express willingness in the past, polite request, preferences/desires, offers and invitations.

https://open.books4languages.com/english-a1-grammar/chapter/would-modals-of-ability