Want to change site URL of my wordpress application

Hi,

I want to change site url of my wordpress application. My wordpress application is inside ‘public_html/blog’ that’s why url of my application containing /blog, but I want application web url should be like https://www.example.com .I don’t want to change wp files location, all files and folders should be on same location in side /blog only want to change site url(browser url). I tried to change url from Dashboard->settings and in wp-config.php file but not working giving ‘HTTP 500 error’. Please help me.

Thanks.