Getting started confused

Hello ,

I’m Diego and I have been browsing themes for my new website that I’ve been anxiously wanting to create. I am very new to this whole website creation thing , but finally figured out domain , host , and such . After buying the 49$ HB theme I have hit a ceiling . I’m stuck I do not understand how to start using the theme on my wordpress. I did try going to appearance then upload new theme , but when I browse my computer I do not have the zip file that you are suppose to upload in order to have HB theme integrated into WordPress . Can you please help me guide me where and how to find and upload this zip file .

Thank u so much.