How to use rays after creating them?

Im trying to make a gun so i made this script (you dont need to read it lol):

    local pistola = script.Parent
    local hole = game.StarterPack.Pistola.Hole
    local mouse = game.Players.LocalPlayer:GetMouse()

    -- Lista de Valores --
    local ammo = 12
    local maxAmmo = 64
    local damage = 20
    local headshotDamage = 50
    local range = 100
    -- impedir spamming --
    local spam = false

        -- Disparo --
        pistola.Activated:Connect(function()
            if spam == false then
                 spam = true
                pistola.Handle.Disparo:Play()
               local bullet = Instance.new("Part")
               bullet.Size = Vector3.new(range,0.25,0.25)
               bullet.Position = hole.Position
               bullet.Transparency = 0.5
               bullet.CanCollide = false
               bullet.Anchored = true
               bullet.Parent = game.Workspace
            wait(0.5)
            bullet:Destroy()
                spam = false
            end
        end)

But then i couldn't set the position so i asked another question at this website and i found out i have to use a ray so i ended up with this new script:

    local pistola = script.Parent
    local hole = game.StarterPack.Pistola.Hole
    local mouse = game.Players.LocalPlayer:GetMouse()

    -- Lista de Valores --
    local ammo = 12
    local maxAmmo = 64
    local damage = 20
    local headshotDamage = 50
    local range = 100
    -- impedir spamming --
    local spam = false

        -- Disparo --
        pistola.Activated:Connect(function()
            if spam == false then
                 spam = true
                pistola.Handle.Disparo:Play()
               local bullet = Instance.new("Part")
                    local ray = Ray.new(hole.CFrame.Position, (mouse.Hit.Position - hole.CFrame.Position).Unit*number)
               bullet.Size = Vector3.new(range,0.25,0.25)
               bullet.Position = hole.Position
               bullet.Transparency = 0.5
               bullet.CanCollide = false
               bullet.Anchored = true
               bullet.Parent = game.Workspace
            wait(0.5)
            bullet:Destroy()
                spam = false
            end
        end)

But it didn't work either so i went to watch some tutorials about making guns on roblox and i found out that they used raycasting too, so im trying to find out how to use my ray. Pls explain me how to use the ray and also a fix if you could. :D