How do I edit a script from a plugin script?

I need help. I went to another post made 3 years ago and it had this important line. Let me make it my way.

script1.Source = script1code

Full code:

btn1_1.MouseButton1Click:connect(function()
    local script1 = Instance.new("Script",workspace)
    local script2 = Instance.new("LocalScript",script1)
    script1.Name = "Shift to Run"
    script2.Name = "SprintScript"
    script2.Disabled = true
    local script1code = [[ … ]]
    local script2code = [[ … ]]
    script1.Source = script1code
    script2.Source = script2code
end)

I haven't tested it yet so I do not know the results but if you have any better ideas please let me know! - CrastificeDude612 :)