To run that query in grafana do the following:
Click on the + sign near the top right of your dashboard
Select 'New Dashboard'
Click on the 'Add Visualisation' button
Click on Teslamate to choose that as the data source
You should then be presented with a page similar to this:
View attachment 1030351
Near the top right there is a dropdown box called 'Time Series' If you click on that you'll get the option to change the panel type (technically visualisation) Click on 'Table'.
Near the bottom left are two Tabs. One says 'Builder' and one says 'Code'. Click on 'Code' tab and you should be presented with a box that has a solitary line in it starting with 1. Paste Cwanja's code into that:
select id, name, vin, inserted_at from cars;
Hit the 'Run Query' button and you should get a list of cars in your database. Hopefully more than one.
Let us know if you see two cars and that the VINs are different (no need to share the VIN with us.)