help my cory cats are laying eggs

Firstly can we establish what type of Corys you have?
In the meantime they should, if one of the more 'common' types, have stopped laying by now.

Are there other fish in the tank? - They, and the Corys, are very adept at eating the eggs so you will really need either to remove the fish or the eggs. The latter option isn't as daunting a task as it might at first sound. You can either remove them from the glass/filters etc with something like a sharp razor blade or, if your nails aren't trimmed too low, pick them off that way.
When the eggs are a few hours old the 'shell' hardens and they become quite manageable.
I note that you have them in a quarantine tank so hopefully they will be the only fish in it. Then you'll just be able to remove/isolate the Catfish and leave the eggs to hatch naturally...
They ought to start hatching after the third day but there will be absolutely no need to try to feed them for at least two, probably three days afterwards as the little fry at first feed off the nourishment within the yolk sac.
Afetr you see them actually swimming around 'grubbing' for food you can then start to feed them (tiny amounts at first) of either commercially available fry food or you can crumble some flake to a powdery consistency and use that.
Spotless water conditions are an absolute must - as is so with all fry - so small daily water changes become an 'essential'.

Good luck with the eggs, keep the Forum informed of how things are progressing.

John