How to wire the other blk wire and the red wire. And how do the two blk wires that are attached to the?

I'm attempting to change an existing switch that operates two lights in a bathroom, to a GFI outlet with a switch to operate the lights. The existing wiring is a three wire (blk is feed, the red ties the two lights together and the neutral. The new GFI and switch has two blk wires on the bottom I know the line blk wire goes to the gold screw and I think the whites get tied together. But I'm not sure how to wire the other blk wire and the red wire. And how do the two blk wires that are attached to the GFI come into play..How to wire the other blk wire and the red wire. And how do the two blk wires that are attached to the?There are two ways to do it. If you don't need the GFCI to protect the lights, just run the black wire to the light switch and the outlet. If you do want protection for the light, run a wire from the output terminal on the GFCI to the switch.How to wire the other blk wire and the red wire. And how do the two blk wires that are attached to the?If the GFCI has a switch, the you need to connect the two red wires to the lights to the output or copper screw and the white wires to the silver screw. The input will go to the other copper screw or to the input leads. The GFCI works by detecting impedance between the three sides, hot/power, neutral or white and green, or ground. All three must be connected to it on the input side. The red wires are the ones that need to be switched. You can connect the neutral from the lights to the neutral side of the GFI on the output. Otherwise it won't be working right.