@gappiah is correct, switching themes is not like changing shoes, things will not fit, settings will be different, content layouts not working, custom CSS will be missing and images may not display the same way, because each theme determines its own way of how content is laid out on the website and how the site will function. No one theme is the same as the next, even with the same theme developer.
The only things that remain the same are the core settings to each page and post determined by WordPress core files and how the Admin area works.
If you want to use a different theme, you need to redo each page / post to display content the way you want, including the home page.
Keep in mind, switching themes can be problematic with plugins, a different theme may not be compatible with the list of plugins you currently use, especially page builders, for example; WPBakery (Visual Composer).
As a backup, keep at least 1 WordPress default theme, you will need it to troubleshoot WordPress issues.