It's so frustrating to open a template, and see that it isn't working, even after adding your media!
This is caused by a common bug in DaVinci Resolve. DaVinci doesn't generate a font error, instead it replaces the font with a bothersome black shape.
Here is one quick way to fix the issue:
Select the text element from the timeline.
Select any other font from the Fusion Control panel, and you should see the text appear. I used Arial as an example in the screenshot below.
Once you have selected any other font, you can change it back to the default font or any font of choice.
If the above solution doesn't work, try installing the downloaded template's fonts which are linked in the Font document in the Font folder.
Finally, if you are using DaVinci Resolve on an M1 chipset Mac computer make sure you check for any updates to Resolve or to OSX. There are some additional issues with the M1 and Resolve, but Black Magic Design is working to fix them in new updates.