Installation:

1. Download the included Python script file
2. Go into Blender. Click on "Edit" on the top left, then click "Preferences" from the drop-down
3. Go into the "Addons" tab, and click on the "Install" button on the upper right hand corner
4. On the file browser, navigate and select the Python script you just downloaded, and click on the blue "Install" button on the bottom right of the file browser window
5. Close the "Preferences" tab and while hovering over the viewport hit "N" to bring up the side panel, and you should see the "Vertex2Light" category

How do I use this add-on?

Once you click on the Vertex2Light category, you will see a panel. You'll notice there's 4 buttons, one for each type of light available. Below that, you'll find all the properties you can use to edit the lights -- these properties will edit all the lights you've added. You'll see property sliders to edit the X, Y, and Z euler rotation, a slider for intensity, and finally, a color wheel for the color.

In order to add a light, you'll first need to select a vertex. Head into your object and select any vertex that you want a light on, then you can simply click on any of the buttons that add a light, depending on which light you're currently needing. There's 4 different types of lights you can add: point light, spot light, area light, and sun light. 

Note: If you don't have any objects in your context collection, all the "Add Light" buttons will be grayed out and you won't be able to click on them. In order to use them, you have to add a primitive mesh to your scene.