Thanks for reaching out.
Welcome to Pro , first, you'll have to install it to your Wordpress, please follow this https://theme.co/apex/forum/t/setup-theme-installation/54
Then in the case in the future, you wish to implement customization then I recommend doing this as well https://theme.co/apex/forum/t/setup-how-to-setup-child-themes/57
And once it's all done, it's best to test and try it directly by looking and checking the demo, you can import your own demo like from here https://theme.co/apex/forum/t/setup-demo-content/56
And then you can edit and test any existing pages, settings, and features from that demo. It can't be done in a single night but once learned, it's really worth. And experience is the best teacher
And if you have questions regarding the features then you can always check our knowledge base here https://theme.co/apex/forum/t/knowledge-base-overview/287 and it should further help you. You can also contact us here in the forum for issues, we can't answer them all at once but we'll more happy to help you for each of your question in each thread