frank eg bonita

So yesterday i traded some coil-overs for a d series vtec head... And noticed a few problems and have some questions... Ok so he said the head came off a blown block so does this mean that the head is blown? What are some ways i could tell that I've got a bad head? What are some things that i could check? Ive also noticed some rust in one of my spark plug holes... And where the valve cover bolt goes broke so is there anyway to fix this?