Scheduling and managing events using Outlook.com calendar
I'm not sure if this will solve your problem, but there is a way to sync contacts between gmail and Outlook. This has nothing to do with iCloud, however. Once you sync your contacts in Outlook, you can then add them to your iCloud address book (within Outlook) and then they will sync with iCloud. However, any changes made to either to your iCloud or your gmail address books after the sync will have to be added to one or the other manually.
The following link is to an article about an open source program that allows syncing between gmail and Outlook. I've used it before and it worked for me. I hope it helps with your issue.
https://www.howtogeek.com/202090/how-to-automatically-sync-contacts-between-outlook-and-gmail/
Good luck!