How to repair this particular toilet flange

[Cjccmc]

Metal portion is rotted out in one place but doesn't remove easily. I can't figure out the raised lip all around the opening (3.75" ID), haven't seen that in repair videos. Top of red metal flange about 3/8" below top of finished floor. Flange seems stuck to drain pipes below. What is the easiest good repair? Limited tools and skills here.

 

[Breplum]

there are a variety of repair flanges. one with hinge on one side could work. ultimately you will need solid wood to attach to, using stainless steel or brass screws.