I need to remove the timing cover and I was wondering if any knows if it is necessary to remove the cylinder head, oh this is a 90 toyota 4runner with a 22re.

 

not necessary to remove the head. just look out for the bolt hidden in the puddle of oil near the front of the cylinder head.
but you have to decide to remove either the head or the oil pan- one or the other has to go.

 

I've already removed the oil pan because I thouht I had bad oil pump but the pump looks good, I did find broken pieces of plastic and metal figured that it might be from the timing chain dampers but I wasn't sir if I had to removed the head or just the valve cover to get to the top bolt

 

You do not have to remove the oil pan OR the head. I have done many timing set changes without removing either part. My 1986 4Runner is going on 5yrs on that swap with no leaks or problems.

The valve cover and the cam bolt/sprocket have to be removed to get to the "hidden bolt"