To install a theme in WordPress:
1. Log in to your WordPress dashboard.
2. Navigate to "Appearance" on the left sidebar.
3. Click on "Themes."
4. Click the "Add New" button.
5. You can either search for a theme or upload one in ZIP format.
6. Once you find your desired theme, click "Install."
7. After installation, click "Activate" to make the theme active on your site.
Remember to explore and choose a theme that fits your site's design and functionality requirements.