It's how you configure your server, most likely you're on apache. Your apache config files will need to enable SSL after you have purchased your certificate you will need to move them to your apache folder on your server and inside the config file you will point to the SSL cert.

There are many tutorials out there, but all I am saying is it has to do with the virtual hosts and the server that serves your wordpress site, not with wordpress itself.

Is your whole site going to use SSL? If so, then just make you have a redirect in place for http to the corresponding https page.

Once you've done with your SSL certificate and your company approves that. Go to the settings of Woocommerce
Woocommerce > Checkout and give checkmark to "Force secure checkout" and update it!. Now you will see your checkout page in https.

Hope this answers your question.

Thanks