all所有 before a noun means "all of, every single" — the whole set, usually a sizable one. It pairs with all / both都 in the predicate, the (modifier / structural particle)的 is usually present, and — crucially — you negate it with no不是, not not不.
Structure: 所有 + (的) + Noun + 都 …
all所有the people人都left走了吗?
Has everyone left?
our我们school学校all所有的teachers老师都can会speak说English英文。
All the teachers at our school can speak English.
Remember: all所有…all / both都 = "every single one" (stronger than a bare all / both都). To say "not all," negate the whole with no不是: no不是所有人all / both都… ("not everyone…"), never 所有人all / both都not不… (which means "none of them…").
Watch out
- 所有人all / both都not不to go去 ("none go") vs no不是所有人all / both都to go去 ("not all go") — where the not不 / no不是 sits flips the meaning.