This is a datapack, it can easily be used in any world or server without any difficulties.
Simply drop the downloaded zip file in the "datapacks" folder of your world save (<world>/datapacks).
Then open your world and do
/reload

In case the datapack doesn't automatically get enabled, run:
/datapack enable "file/[​datapack folder name].zip"

I test all my creations, but bugs happen no matter how long you test something. Whenever someone experiences a bug, I do my best to fix the issue. You can help me by providing any useful information. You can never give me enough information, but please send it in a DM instead of placing it in the comments. You can still place a one-liner in the comments stating the issue to make the community aware, but that alone isn't enough to help me fix the issue.

• Checklist: Are you using the right version? Did you do /reload after dropping the datapack in? After /reload, does the datapack show up green in /datapack list?
  
• What is the issue? Does the datapack not seem to be working at all or is there a specific feature you are having issues with?
  
• What happened? Please give me all the steps needed to reproduce the issue. The faster I can experience it, the faster I can solve it.
  
• What did you expect to happen instead? This helps me understand your point of view and determine if the issue described is actually the issue I need to fix. The bug you are experiencing could just be a side effect of something else that doesn't behave as expected.