Choose a name for your Profile (This can be changed later on).
Open the CurseForge Launcher, if you have not installed the launcher follow this guide. These steps will get you set up with a profile that you can use to experiment with your modpack. How to Create a Custom Profile in the CurseForge Launcher
What Happens When We Have Your Modpack Files.
How to Add Mods to the Custom Profile in the CurseForge Launcher.
How to Create a Custom Profile in the CurseForge Launcher.