A child theme is a theme that inherits the functionality and styling of another theme, called
the parent theme. If you modify a theme directly and it is updated, then your modifications may be lost.
By using a child theme you will ensure that your modifications are preserved.

Hotel WP provides an available child theme so that you just need to upload
to your site without doing anything else after installed the parent theme successfully. Child theme of
Hotel WP is a zip file named hotel-wp-child packed in
child-theme folder after exacted theme package (child-theme/
hotel-wp-child)
. Uploading child theme is similar to uploading parent theme.

Step 1. Appearance >> Themes >> Add New.

Step 2. Click Upload Theme
button.

Step 3. Browser child theme hotel-wp-child.zip
file in child-theme folder and click Install Now
button.

Step 4. Active child theme.

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If you want to learn more about child theme and how to modify it, you can refer these links:

Codex WordPress about Child Theme.

WordPress Developer
Theme Handbook
.