1. You need to install Spigot or Craftbukkit to accept plugins. You can read how to change your server here => https://www.minecraft-hosting.pro/tutorials/read/12
2. Go to "Plugins" panel.
3. Search "Votifier" in search tab.
4. Click on "download" button to install it.
5. Go to "FTP" panel. Enter in this directory .../plugins/Votifier/
6. Click on "edit" button for config.yml file
7. Enter in host: your IP without the port (for me it's 220.127.116.11)
Enter one port between 31000 and 32500 (I have chosen 31000, you can put 31001, 32499...)
8. Click on the green arrow to save changes.
9. RESTART server
10. Go to "Console" panel.
11. Check in the live console, if you don't have any error. For me it's ok ;)
12. Connect to your server with Filezilla an FTP client, in order to recover the votifier's public.key.
13. Go to directory .../plugins/Votifier/rsa and open with Notepad the votifier's public.key file.
You can make a right click and View/Edit or drag and drop to your desktop in order to open with bloc note.
14. Copy all the public key.
Go to this website https://www.minestatus.net/votifier/test
15. Enter your server IP (for me it's 18.104.22.168)
16. Enter your port that you had chosen (for me it's 31000)
17. Paste your public key that you had copied.
18. Click on Test button to see if connection is working.
19. Success !