You shouldn't need a tutorial for it, Installation Tab -> New -> Select Minecraft Version, Game Directory (where you want mods, logs, and a configs to be generated), and Java version -> Save -> Play
This is starting to go from "Support and Bug Reports" to "Mods" if you want to make a thread that advertises your mod please do so in the correct subforum instead of your support thread.
The filenames of one or more of your mods suggests you got them from a repost site.
Please read up on the StopModReposts project (link in my signature) for info on why this is a bad thing.
Forge installs itself as a version of Minecraft.
Make a new Profile/Installation and select Forge from the version dropdown.
(Note: For some reason Forge 1.12.2 gets booted to the bottom of the list.)
Give a URL, many sites pretend to be the official website to get you to click on their links, often providing mislabeled and outdated versions such as the one you have.
The dev was using over-shortened mod IDs and changed them, netherex used to be nex and libraryex apparently used to be lex. Try the most recent versions of both.