Life insurance can be purchased on someone who is dying but the type of life insurance you can buy for a dying person is guaranteed issue life insurance.
The person the life insurance is being bought for my be expected to live though for at least 2 years after purchase of the life insurance.
So if the person is dying within a few months to a year then getting life insurance is gonna be near impossible.
It's best to have life insurance in place way before you're expected to die so that your funeral expenses and other final expenses are taken care of.
Waiting until someone is dying before getting life insurance is the worst way to get life insurance although you can sometimes find life insurance when someone is dying.
Or pay the funeral home directly for the burial expenses through a monthly payment plan.