how can i download everything from iCloud to my new ipad ?

If you mean that you want to use an iCloud Backup to set up the new iPad, see instructions in Use iCloud to transfer data from your previous iOS or iPadOS device to your new iPhone, iPad, or iPod touch - Apple Support

If you mean that you had data synced to iCloud (e.g., iCloud Photos, Contacts, etc) and want that to sync to your new iPad, turn on the same sync options in your new iPad (at Settings > [username] > iCloud. See, for example, Set up and use iCloud Photos - Apple Support