3 pot lights stopped working after I cut the circuit breaker. They activate together. I replaced the "full slide dimmer" thinking I burnt the fuse out. Still nothing.

Are there only 3 lights on the breaker? If so, make sure you reset the breaker? If not, do the other outlets or lights work? Is there a tripped GFCI? Sometimes people put lights on the load side of a GFCI.

Try bypassing the Dimmer.

Let's start at the beginning, please. Exactly why did you "Cut" the breaker and exactly what do you mean by the term "cut?