For both security and SEO reasons, it is recommended for all websites to load using HTTPS - that is, the secure version of HTTP, which is the underlying protocol used for transmitting data between a web server and a user's browser.
If your WordPress website fails to load with HTTPS altogether, or if the website appears distorted when accessed via HTTPS, you can fix it by following these steps:
Step 1 - Install an SSL
If you have a VPS, make sure to install an SSL for your website according to your operating system instructions before proceeding to the next step.
Step 2 - Update the WordPress URL
Log in to your WordPress Admin area and click on Settings in the left menu:
Next, update URLs from HTTP to HTTPS in the WordPress Address (URL) and Site Address (URL) fields:
Scroll down and click on the button to save the changes - your website will load now with HTTPS.
Step 3 (Optional) - Check for Mixed Content
If your website design appears "broken" after updating the URLs to HTTPS, follow this guide: How to Fix the Mixed Content Error in WordPress.