How can I mod Minecraft, it's just that I really wanted to install a mod pack called Fabulously Optimized, but I really don't like the mod pack installer curse forge because it makes my Minecraft launching process annoying and it has ads
You could always look at the individual mods that make up the modpack, and download them one by one from the curseforge website. You can also download the FTB launcher, download the modpack from there, and copy the files over to your preferred launcher.
Where can I find the FTB launcher?
You can download the FTB launcher from https://feed-the-beast.com/ftb-app
Ok, I have it downloaded on my Windows machine. What should I do now?