Instructions
Launch Roblox Studio. Click "Start," then "Programs" and finally "Roblox Studio" from the desktop of your computer.
Open your project. In Roblox Studio, click "File" then "Open" from the toolbar menu along the top of the software. Navigate to your project, highlight it with your mouse and click "Open."
Select the object into which you wish to place a script. It should appear highlighted on your screen when you click it. Click "Insert," "Object" and "Script" from the main toolbar menu.
Add your script to the object. Navigate to the "Explorer" pane located on the right side of Roblox Studio. Click the "plus" symbol next to the name of your object. Double-click "Script," which appears below the name of your object. Enter the script in Lua language and press "Save."