There are many options for cloud data storage services, and you can check them one by one for the fees in your country – Dropbox, Google Drive, iCloud, are the common ones, and Amazon S3, Microsoft Azure, Wasabi are the more ‘pro’ ones. Check on Wasabi’s web site for a cost comparison between Wasabi and others.
One thing to bear in mind with most cloud services is that they have ‘storage fees’ per month based on how much you’re storing, and ‘egress’ fees means fees per GB for how much you download. Even if you download the same files/folders over and over again, you get charged as often as you download your own data.
So, in my opinion, for 3 TB of data which is likely to increase, you’re better off getting a drive as a backup, and then keeping a clone of this drive at another location, and using a sync service like Resilio to keep them both in sync. Or even physically carrying the ‘off site’ drive to the other drive’s location, syncing them and then moving them apart.
Or, you could get a personal cloud kind of device which is a cloud connected hard drive, and have your own cloud. WD makes such personal cloud devices on which you can add your own drive.