Floor repair to install new tiolet flange

I am looking for some advice on how to best proceed with a problem I uncovered when attempting to replace an old toilet. I removed the toilet and found the flange installed flush to the floor, into a cracked plaster type material, the flange was loose, the screws were rusted and no longer tied to the sub floor. The old installation is a mess. I am a novice would appreciate any advice as to how to best repair the floor and attach a new flange. Thank you.

From what I can see, the flange was not "loose", it was the wrong type of flange for that pipe and would not, and could not, be made "tight" because there is no way to attach it. Call a plumber, have him cut an annular opening around the pipe and lead/oakum a proper flange to the pipe.

Just a couple of points. First, a flange should be resting on top of the the finished floor. You can get by with flush, but since you have to repair the damaged floor and install a new flange anyway, it should be done right. You need to remove as much of the floor and sub floor as necessary and replace all of the damage. You may be able to salvage the tile and reuse it, but the tile under the toilet does not have to be color matched, only the thickness needs to be the same. The tile under the flange can be notched for the screws that hold the flange down before the tile is adhered to the the floor. Drilling later is possible but is a PITA. Check the floor for level before setting the toilet. If it is level, no shims should be necessary. Set the toilet with a single wax ring that does NOT have the plastic funnel or horn, what I call a "plain Jane ring". The new flange should have a stainless steel rim. Avoid the cheap PVC or ABS rims, the can break. Use #12 stainless steel screws to anchor the flange to through the finished floor and at least into the sub floor. Brass is OK, but not as strong as steel. As a novice, you may be wise to have a plumber deal with the installation of the flange after the floor is repaired.