How to fix LocalScript from not reading Character?

Well the error "Players.Cowation.Backpack.Shotgun.Shotgun:5: attempt to index local 'character' (a nil value)" says Character is a nil value. And it Is nil because by looking at your script in the second line;

local character = game.Players.localPlayer.Character

Your forgot to cap the L in LocalPlayer

Also, theres more to it.

If your testing this in the actual game then you have to use WaitForChild() because objects actually take time to load in so the game or studio may not have found Character yet.

so I suggest you do one of these;

local tool = script.Parent
wait(1)
local character = game.Players.LocalPlayer.Character -- local player is fixed ;)
local humanoid = character.Humanoid
local idle = tool.Idle -- Anim Object
local activate = tool.Activate -- Anim Object

local animTrackIdle = humanoid:LoadAnimation(idle)
local animTrackActivate = humanoid:LoadAnimation(activate)

local function onAnimationEquip()
    animTrackIdle:Play()
end

local function onAnimationActivate()
    animTrackActivate:Play()
end

tool.Equipped:connect(onAnimationEquip)
tool.Activated:connect(onAnimationActivate)

that wait is enough time for the objects to load in

or;

local tool = script.Parent
local character = game.Players.LocalPlayer:WaitForChild('Character') -- wait for character to load
local humanoid = character.Humanoid
local idle = tool.Idle -- Anim Object
local activate = tool.Activate -- Anim Object

local animTrackIdle = humanoid:LoadAnimation(idle)
local animTrackActivate = humanoid:LoadAnimation(activate)

local function onAnimationEquip()
    animTrackIdle:Play()
end

local function onAnimationActivate()
    animTrackActivate:Play()
end

tool.Equipped:connect(onAnimationEquip)
tool.Activated:connect(onAnimationActivate)

Those can fix your problems, also, Roblox have their own events so you can do tool.Activated:Connect(function() from the top instead of calling a function, that can improve your script.

Last thing is don't use connect it's deprecated, meaning it can be removed use Connect

You can also use CharacterAdded which is the best way

so it would be like this;

local tool = script.Parent
local character = game.Players.LocalPlayer.CharacterAdded:Wait() -- wait for character to load
local humanoid = character.Humanoid
local idle = tool.Idle -- Anim Object
local activate = tool.Activate -- Anim Object

local animTrackIdle = humanoid:LoadAnimation(idle)
local animTrackActivate = humanoid:LoadAnimation(activate)

local function onAnimationEquip()
    animTrackIdle:Play()
end

local function onAnimationActivate()
    animTrackActivate:Play()
end

tool.Equipped:connect(onAnimationEquip)
tool.Activated:connect(onAnimationActivate)

Fix your other little problems and your good to go!

Have fun and good luck developing!

If this helped then please accept answer ;)