To Redirect HTTP to HTTPS add in your .htaccess one of the the following:

1. Redirect All to HTTPS

RewriteEngine On
RewriteCond %{SERVER_PORT} 80
RewriteRule ^(.*)$ https://domain.com/$1 [R,L]

2. Redirect a Specific Domain to HTTPS

RewriteEngine On
RewriteCond %{HTTP_HOST} ^domain\.com [NC]
RewriteCond %{SERVER_PORT} 80
RewriteRule ^(.*)$ https://domain.com/$1 [R,L]

3. Redirect a Specific Folder to HTTPS

RewriteEngine On
RewriteCond %{SERVER_PORT} 80
RewriteCond %{REQUEST_URI} folder
RewriteRule ^(.*)$ https://domain.com/folder/$1 [R,L]

* Replace “domain” with your domain and "folder" with your folders name.