Should I cut off wilted leaves?

Could they come back to life, or is it bad to have these leaves stay on the plant?

Those leaves are done for. The plant looks like it has been starving for a while... once a leaf is affected by nutrient deficiency unless it was mild and treated immediately the leaves themselves do not recover.

plant is dying.
is it in flowering now?!

Yea, its got little buds now.

I'd be getting some more seeds started soon, you're not going to get anything off that. I don't know what you're using for lighting, but it is obviously woefully inadequate. Looks starved for nutes also.

Unless you're just playing around with free bag seed and don't really give a shit one way or the other you need to spend a lot of time reading before dropping the next seeds.

you should veg your plants before flowering. i veg mine for 2 months.
feed your plant and let it grow before attempting to grow buds on it

There should be a plant protective services for these types of tragedies that are shown on here.