This is the 1646th most frequent Russian word.
им
"Им" means "to them" or "them" (dative case of "они" - they).
The word 'им' is used here as the dative case pronoun for 'they', functioning as an indirect object.
Я рассказал им всё.
I told them everything.
The word 'им' is used here in the dative case to indicate who needs more time, associating with an implied necessity.
Им нужно больше времени.
They need more time.
The word 'им' is used here in the dative case to describe the experiencer of the state 'will be difficult'.