Opening and editing Google docs with Pages and iCloud syncing

Having copied/synced my google drive (nearly 90GB of data) to my new MacBook Air, I was hoping to be able to edit the Docs and Sheets documents with Pages and Numbers. However, that does not seem possible? I did convert one from Docs to Word and then could open it with Pages, but that is a lot of work if I have to convert each doc individually :( I'm hoping there is an easy way round this?

The other question is how do I get my local drive to sync with iCloud? I've purchased the 200GB iCloud, but nothing aa nye seems to copy anything up to the iCloud drove. I'm probably missing something simple as a brand new Apple user. Any suggestions appreciated.

Many thanks!!