Most of the usages of に I've seen have it directly followed by a verb directly attached to it. (The location of existance にある/にいる, The action objective e.g 私は電車に乗りました, etc)
I know there are some that don't directly have に follow a verb, but its still heavily reliant on a verb (私は六時に家を出す出る)
However, に can also be used when there are no verbs in the sentence
私に必要です Or 私には必要です
- I interpret (at least the first sentence) as [smth] is essential to [me] or 私*
I (somewhat) get the fact that に and には mean kinda different things and are to be differentiated, so i will just refer to the first sentence.
What usage does the に fall into here? Is there a certain way it gets applied in any sentence with only a noun/ adjective (as in it gets used the same way/ means the same thing)
Other maybe-related examples i found
タバコは体に悪い。 The way i see it (i guess) is that the に marks that tabacco is 悪い towards/ for the body/体. But why can't we use something like が here?
私に何か用ですか。 I guess this sentence works in a similar way to the 必要 one, labelling 私 as "What will i use/ be in use for me"
Sorry if this seems like an obvious question, but im genuinely stumped.
(Edited to explain how i see it)