Once you have hosting, and WordPress is installed, you are ready to install Appointa. To do this, you need to get the installable file from the appointa.store account, from which Appointa was purchased. There are then a couple of ways to install Appointa; via WordPress, or via FTP. This is a five-minute process that is well explained in these docs and videos.
How To Install Avada Via WordPress
How To Install Avada Via FTP