大多

大多 never glues onto a noun. It's a crowd word that tells you how a whole group behaves, so it lands after the subject and before the verb or 是. Want the English-style label 'most people'? Use 大多数: 大多数人, 大多数学生, 大多数时候. Compare 我们公司的人大多是本地人, which sounds like a real coworker talking, with 大多的人都是本地人, which smells of Google Translate. Same deal in group chats: 我们群里的人大多在加班 beats 大多的人都在加班 every time. If you're stuck mid-sentence and need a noun descriptive word, 大多数 and 大部分 both happily take 的.

“可现在的茶馆虽然还是可以喝茶，但是去那儿的人大多不是老北京。” (But although you can still drink tea in today's teahouses, most people who go there aren't old-time Beijingers.)

很多 counts heads without any group in mind: 这儿有很多外国人 could be ten people out of sixty. 大多 slices a group you already named and says the majority of it: 这儿的学生大多是外国人 sounds more like fifty-five out of sixty. That's why 大多 always needs something after it, while 很多 can stand alone as the whole comment. You can say 去那儿的人很多 and stop; 去那儿的人大多 and stop is a dangling sentence. Keep the difference in mind for complaints too: 我们群里很多人请假 means a bunch of people bailed, 我们群里的人大多请假 means nearly everybody did. One person alone can never be 大多 — you need a crowd to slice.