The "category level".
In FCPX, all effects are organized into categories. Those categories you see are just folders holding the individual templates. So you need:
YourHomeFolder > Movies > Motion Templates > Title > [create a new folder with a category name, or use an existing category folder] > the Title folder goes in here. [Templates are just folders containing at least the Motion project file, two thumbnail images (large.png, small.png) and a Media folder.]
If you created the Title folder, it must be .localized. Right click on the folder and Get Info. In the Name & Extension section, add '.localized' (without the quotes) to the end of the Titles folder name.

Once you get everything straight, you should see your title appear in FCPX (you don't even have to restart).
If the version of FCPX you are using is older than the version of Motion used to create the template, you will still get the missing title icon. You can check the versions compatibility here:
https://fcpxtemplates.com/fcpx-motion-compatibility/#compatibilitytable
and further up that page are instructions you can try to backdate the Motion template. As long as the template doesn't contain anything newer than the older version of fcpx will expect, it should be successful (I've pulled it off a number of times).