When I try to reset this sync password, the opera erased all my cloud info

Yes. Resetting the passphrase at https://www.sync.opera.com/ means to wipe out all your data on the server.

. But the sync option wasn’t synchronazing and it was asking some “password” for sync but I didnt configurate any passwords besides my password’s account.

Sync has been buggy for everyone lately. Users are having trouble logging in and some that can get logged in have trouble syncing passwords or can sync passwords but passwords get corrupted. Seems to be a mess right now.

I lost all my bookmarks Is there a way to recover

If they are still present in one of your Operas, logging in to Sync again and syncing bookmarks should sync that back to the server. But, with Sync being buggy, there's no guarantee.

If you don't have your bookmarks anywhere, goto the URL opera://about, take note of the "profile" path, and look in the profile folder for a Bookmarks.backup" file. You can copy that file (to your desktop for example) and open it in text editor to see if your bookmarks are there or not. If they are, you could take a copy of it, rename the copy "Bookmarks" and use it to replace the existing "Bookmarks" file in the profile folder. That might get your bookmarks back. Short of that though, you're probably out of luck.