Hello,
I have found this [1] tutorial explaining the details about the wordpress hosting in GCP. All steps are well explained. Please note this is not an official video but good to answer all the questions. To know more about the SSL certificate, I would recommend checking this [2] documentation for available options.
[1] https://www.youtube.com/watch?v=cG9kv5-5bPI
[2] https://support.google.com/domains/answer/7630973?hl=en