What would you call a person who doesn't know what they like or will do with their life?

What would you call a person who would always response with 'I don't know' when thinking about their likes, favourite things, or their future (like plans for the next day or what they want their life to be like etc.)

I'm looking for a word describing a person who is and whose personality/ lifestyle is 'undefined'.

My candidate (not quite): the word impersonal

(Merriam-Webster): not existing as a person : not having human qualities or characteristics

(Dictionary.com) having no personality; devoid of human character or traits: an impersonal deity.

I'm not sure if it works here, as in a sentence

'*He never knows what he wants/ needs, he feels like he has nothing going on, he's ________ [like a clean slate]. (=He would describe himself as impersonal*)'

I'd want that adjective to describe someone's void/ emptiness =the lack of fundamental qualities that makes person a person (not the words for simply not being interesting or being lifeless like dull or lacklustre)

As suggested in comment by Dan Bron : aimless.

Lacking direction or aim; purposeless; desultory; (also) without the means of taking aim

OED

Albert Einstein’s best ideas came when he was aimless. Yours can too

qz.com

I've seen rudderless used in this context.

'He doesn't know what he wants/needs, he has nothing going on; he's rudderless.'

ODO:

rudderless
ADJECTIVE

1.1 Lacking a clear sense of one's aims or principles.

‘But doesn't all this leave us dangerously rudderless, drifting on relativistic seas?’

‘Entering their thirties, the men are stuck in adolescence, rudderless, jobless, and harboring dreams of escaping their small town - dreams they never act on.’

‘A bit rudderless and uncertain about his future prospects, Saleem falls under the influence of fundamentalist agitators, who operate under the patronage of the local landlord.’

Macmillan:

rudderless
ADJECTIVE

lacking any clear aim, purpose, or direction

Indecisive, as in:

• prone to or characterized by indecision
• not clearly defined, indefinite