By default, once your SSL certificate is installed, visits to the non-secure version ("http://www.tudominio.com") will not be automatically redirected to the secure version ("https://www.tudominio.com").
Here's how to configure in WordPress the automatic redirection to "https", or in other words, from port 80 (http) to port 443 (https).
The "Really Simple SSL" plugin allows you to perform this configuration in an extremely simple way. All you have to do is proceed with the installation:
Access the Wordpress administration panel. This is usually located in the "wp-admin" directory, for example:
In the left menu, click on Plugins > Add new and in the search field enter "really simple ssl":
You have now configured the automatic redirection to "https"!