1

First Step

Go and Download CurseForge on your PC.

2

Second Step

Choose Minecraft as Game.

3

Third Step

Click Create Custom Profile.

4

Fourth Step

Click Import a previously created profile.

5

Fifth Step

Select your Modpack.zip.

6

Sixth Step

Wait for forge to Validate the manifest and build the modpack.

7

Seventh Step

Right click the modpack and click on open folder.

8

Eighth Step

Once you are at the folder copy the config folder and mods folder and upload those to your server through SFTP or archive(zip) them and upload them through the panel and un-archive them.

Also make sure the mods are first compatible for a server!