Your site is secure, and it stays that way on its own. You'll never have to do a thing.
A browser shows a little padlock, or the words "not secure," based on whether the connection is protected. Every site here comes with that protection built in.
The security certificate that makes the padlock show is set up and renewed for you. That covers your own web address too, once it's connected. Nothing to install, nothing to renew, ever.
One normal hiccup: right after you connect your own web address, the browser may briefly say "not secure" while the certificate is being set up. Give it a little while and refresh the page.
If it's still saying that a day later, contact support. Click Get help on your account page.
Why this matters
Customers, and Google, trust the padlock. A "not secure" warning scares people off before they read a word. Yours shows the padlock automatically, so you look trustworthy from the first click.
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