1

Download the .rbxm file

In #commands, run /retrieve Orbit and the Parcel Bot should send you a link that redirects to the file once you authorize with Discord.
The “Orbit” in the command has to be under the productname parameter!
2

Insert the file

Once in Roblox Studio and the .rbxm file downloaded, press right click anywhere you want, and on the Context Menu hover/press on Insert and press Insert from file, then select & open the .rbxm file you just downloaded in the newly opened File Explorer. You can also just drag the file from your File Explorer into Roblox.
3

Parenting the Folders

After inserting, you’ll have a new Folder called Orbit in your Roblox Explorer, expand that and the MainFiles too, then you’ll see two important Folders: OrbitServer & OrbitStorage. Do not rename them! Parent OrbitServer into ServerScriptService, and OrbitStorage in ReplicatedStorage. After doing so, you can delete Orbit and MainFiles Folder. (neither of which should have any special content.)
In order for Orbit to appear in your game, you must authorize players/groups. You can find the guide here.