The belt just spawns in and gets flicked away, i'm guessing it flicks like that because it was inside of another touchable part and not welded to it.
local Players = game:GetService("Players")
local ReplicatedStorage = game:GetService("ReplicatedStorage")
local LobbyBelt = ReplicatedStorage.LobbyBelt
Players.PlayerAdded:Connect(function(Player)
local Character = Player.Character or Player.CharacterAdded:wait()
local Belt = LobbyBelt:Clone()
Belt.Parent = Character
Belt.CFrame = Character.LowerTorso.CFrame
local Weld = Instance.new("ManualWeld")
Weld.Parent = Belt
Weld.Part0 = Belt
Weld.Part1 = Character.LowerTorso
Weld.C0 = CFrame.new(0, 0, 0)
print("Player Equipped the Lobby Belt")
end)

4 comments
also u need to update the Belt.CFrame constantly otherwise it wont follow the player
Great now the belt just falls straight through the floor.
The flinging away isn't the issue, the flinging away is just a result. A result of the Belt somehow not getting welded. And like my question asks I'm looking for a way to fix the weld.
CFrame is used to change the position of something, it doesnt hold any numbers but it needs numbers to put whatever u wanna change the location of to that location