Problem displaying templates

[vegasy]

Dear Friend :
I have a wordpress version of the latest version, I try to create a website ... but every time I install a new template, it appears empty without the internal content of the template ...
I have inserted the template from the installed template package by default so that you can preview the problem on my site ..

​https://trainwithus.net/

Note that I did not install any add-on

[joyously]

Your screenshot shows the Theme Repository. You can install themes, but they have no effect until you activate them. And a theme simply styles your content. It does not provide content (unless it has some starter content, which only works on a fresh site and is published from the Customizer).

[vegasy]

Replying to joyously:

Your screenshot shows the Theme Repository. You can install themes, but they have no effect until you activate them. And a theme simply styles your content. It does not provide content (unless it has some starter content, which only works on a fresh site and is published from the Customizer).

Dear Friend
I have inserted some content within the template but it remains the same

[vegasy]

Replying to joyously:

Your screenshot shows the Theme Repository. You can install themes, but they have no effect until you activate them. And a theme simply styles your content. It does not provide content (unless it has some starter content, which only works on a fresh site and is published from the Customizer).

Is it not necessary when installing a new template to include the content included in the template

[joyously]

Themes are not templates. Themes do not provide content.
The content you see in the preview is part of the preview site content, so that all the themes being previewed will show the same thing, styled as that theme styles.