I Don't understand, I got everything set up but It wont work in player?

First of all,

game.Players.LocalPlayer

is only accessible from the Client, in Filtering Enabled.

Some parts of your script is FE compatiable and some isn't.

You should think about structuring your code, so first of all you need to look at the fact that this is non FE. This means that everything can be done from a LocalScript in StarterPlayer.

Another thing is that

:connect

is deprecated, you should be using

:Connect

You seem to want to change the clothes based on which GUI you choose. Here's how I would do this (local script in game.StarterPlayer.StarterPlayerScripts

local Player = game.Players.LocalPlayer
local PlayerGui = Player:WaitForChild('PlayerGui')
local GUIButton = PlayerGui.-- Locate this to your GUI button

GUIButton.MouseButton1Click:Connect(function()
    if Player.Character then -- Checks if there is a Character
        -- Do your custom changes.
    end
end)

To begin with, you should probably used WaitForChild() instead of FindFirstChild() for the character because the character doesn't load all in at once. Because this is a local script, the PlayerAdded event is unnecessary. You should also put the uniforms in ReplicatedStorage because local scripts cannot access ServerStorage. Below, I have refactored the code a little bit by implementing the fixes, removing deprecated functions and adding more variables to increase readability.

local player = game.Players.LocalPlayer
local playerGui = player:WaitForChild("PlayerGui")
local screenGui = playerGui:WaitForChild("ScreenGui")
local repStorage = game.ReplicatedStorage
local uniformG = repStorage:WaitForChild("UniformG")

player.CharacterAdded:connect(function(char)
    local torso = char:WaitForChild("Torso")
    local head = char:WaitForChild("Head")
    local leftArm = char:WaitForChild("Left Arm")
    local rightArm = char:WaitForChild("Right Arm")
    local leftLeg = char:WaitForChild("Left Leg")
    local rightLeg = char:WaitForChild("Right Leg")


    screenGui.GOB.Girl.MouseButton1Click:Connect(function()
        screenGui.BegineChoose.Prisoners.MouseButton1Click:Connect(function()
            wait(1)
            for i , v in pairs(char:GetDescendants()) do
                if v:IsA("CharacterAppearance") or v:IsA("Accoutrement") then
                    v:Destroy()
                end
            end

            for i , v in pairs(torso:GetDescendants()) do
                if v:IsA("Decal") then
                    v:Destroy()
                end
            end

            local hat1 = uniformG.Hats1:GetChildren()
            if #hat1 > 0 then
                local i = math.random (1,#hat1)
                hat1[i]:Clone().Parent=char
                hat1[i].Handle.Position = char.Head.Position
            end

            local hat2 = uniformG.Hats2:GetChildren()
            if #hat2 > 0 then
                local i = math.random (1,#hat2)
                hat2[i]:Clone().Parent=char
                hat2[i].Handle.Position = char.Head.Position
            end


            local hat3 = uniformG.Hats3:GetChildren()
            if #hat3 > 0 then
                local i = math.random (1,#hat3)
                hat3[i]:Clone().Parent=char
                hat3[i].Handle.Position = char.Head.Position
            end

            local shirts = uniformG.Shirts:GetChildren()
            if #shirts > 0 then
                local i = math.random(1,#shirts)
                shirts[i]:Clone().Parent=char
            end

            local Pants = uniformG.Pants:GetChildren()
            if #Pants > 0 then
                local i = math.random (1,#Pants)
                Pants[i]:Clone().Parent=char
            end     

            local bodycolor = uniformG.BodyColors:GetChildren()
            if #bodycolor > 0 then
                local i = math.random(1,#bodycolor)
                head.BrickColor = bodycolor[i].Value
                leftArm.BrickColor = bodycolor[i].Value
                leftLeg.BrickColor = bodycolor[i].Value
                rightArm.BrickColor = bodycolor[i].Value
                rightLeg.BrickColor = bodycolor[i].Value
                torso.BrickColor = bodycolor[i].Value    
            end

            local faces = uniformG.Faces:GetChildren()
            if #faces > 0 then
                for i , v in pairs(head:GetChildren()) do
                    if v:IsA("Decal") then
                        v:Destroy()
                    end
                end
                local i = math.random(1,#faces)
                faces[i]:Clone().Parent = head  
            end

            local packages = uniformG.Package:GetChildren()
            if #packages > 0 then
                local i = math.random (1 , #packages)
                for i , v in pairs(packages[i]:GetChildren()) do
                    v:Clone().Parent = char
                end
            end
        end)
    end)
end)