2000 Honda Civic ex brake driver brake fluid

The front brake calipers are very simple devices. The fluid goes into one hole (the brake hose attachment) and goes out one of two other holes (the piston bore or the bleeder hole). If the caliper is not bleeding and the input seems fine, check the bleeder hole.

If you have the brakes assembled (i.e. brake hoses connected), do the following:

Unscrew the bleeder completely on the bad caliper and take it out of the caliper. Inspect the bleeder threads - are they covered in rust? When you take the bleeder out, brake fluid should start coming out of the bleeder hole. Bleeder hole is big enough that it should never be plugged. What may happen is the bleeder is seized in the caliper and trying to take it out just breaks it in two, at which point you need to either extract the rest of the bleeder out of the caliper or get a new caliper.

With the bleeder out of the caliper:

Take a paperclip and straighten it. Insert the paper clip into each of the bleeder holes as far is it will go. Wiggle it around. Is any dirt/rust coming out?

Take some brake cleaner and attach a straw to the can. Spray brake cleaner through the straw into each hole in the bleeder. The fluid should come out of the other hole.

Reassemble the caliper and try bleeding it again.

Note: if any part of the braking system is disassembled (e.g. brake lines disconnected, anything other than purely bleeding the brakes) you should bleed all 4 corners starting with the one furthest from the master cylinder.