broken main pvc pipe

hi. i am new here and also to plumbing....i am trying to tile my bathroom-haven't started yet though....the problem at this time is my toilet flange. when i took the toilet up, it was broken....when i tried to get this up, i found it to be glued to the main pvc pipe and no screws were added. in breaking this out, i have broken off about 2 inches x2 in. (a v shape) out of the main pipe.....my question is: what do i need to fix this? my existing floor is vinyl and i am currently trying to get this up as well, but found some black almost like small roots when i took the vinyl up around the toilet....is this normal? any help would be greatly appreciated....currently i just put the broken piece with flange on back in place and put a plug in sewer hole....

This is not an easy first plumbing repair. I believe you'll need an internal pipe cutter to cut out the PVC pipe past the point where it is broken. Then you'll need to glue an extension piece with a new flange attached. The flange needs to be level with whatever new floor you are putting in. As far as the black roots, Why don't you post a photo. You may have had a toilet leak, and this is some nasty black mold. Wear a dust mask and gloves when handling it.

thanks! i would bet on the mold since this toilet was leaking for a while before i took it up....before we bought this house, the previous renters looked like they had let all the bathroom tubs run over and there is a blue discoloration under the vinyl flooring in 2 bathrooms. is the tool very expensive to repair this? i couldn't just put a sleeve in to cover the broken area? wish i had spoken to you before i picked up that mold.... i should probably keep a face mask on during all my work.....

One version of an internal pipe cutter looks sort of like a small circular saw blade - you use it on a drill (carefully!). Not much money. Is this on a slab, or a wood framed floor? Can you open the ceiling under it?

this is a slab. i am toying with letting a professional do this job just to make sure it is done right, but i haven't decided yet.