Ahh I got it. On the main domain: tilyexpress.ug, you also have the data, and contents, right?
And now you want to install the Uminex theme on your site without losing all your own data and contents.
If that, it would be in the INSTALLATION SERVICE service. Because here we will just help the customers to install the theme normally by importing the demo data as in the Documentation we have. So if we do the job for you, we have to upload the theme package, import every single page and modify it to be the same as the demo. It's not included in the Support service.
Hope you understand it.
Or you can backup all your own data, then we will install the theme, and import the demo data for your site. And then you can upload/import again all your own content.