To redirect all URLs from www to non-www and also to redirect from http to https, this code snippet to be added to .htaccess file at the top should do the trick.
So https://example.com
# BEGIN Redirects
RewriteEngine On
# 301 redirect www to non-www
RewriteCond %{HTTP_HOST} ^www\.(.*)$ [NC]
RewriteRule ^(.*)$ https://%1/$1 [R=301,L]
# 301 redirect to https
RewriteCond %{HTTPS} off
RewriteRule ^(.*)$ https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]
# END Redirects
If you still want the www way instead https://www.example.com
# BEGIN Redirects
RewriteEngine On
# 301 redirect to www
RewriteCond %{HTTP_HOST} !^www\.
RewriteRule ^(.*)$ https://www.%{HTTP_HOST}%{REQUEST_URI} [L,R=301]
# 301 redirect to https
RewriteCond %{HTTPS} off
RewriteRule ^(.*)$ https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]
# END Redirects
