I want to get all my photos off icloud and cancel icloud. How do I do it?

tygb already explained many relevant points.

Basically, if your photos are in iCloud Photos and you want to save the albums and captions you created in your iCloud Photos Library, you need to sync a Photos Library on your Mac with iCloud Photos. The library on your Mac must not use the "Optimise Mac Storage" feature for iCloud, so all photos will be downloaded locally. And the Photos Library needs to be on a volume with enough free storage to accommodate the full library. The local library will need more storage than the library in iCloud, expect it to be 25% or more larger than the iCloud version, because it needs to store some additional working copies - previews for the media browser, faces thumbnails, etc. If you use an external volume for the library, it needs to be prepared as described here: Move your Photos library to save space on your Mac - Apple Support

Wait until all photos have been downloaded from iCloud, before you disable iCloud. In Photos 4 on macOS 10.14 Mojave you can ctrl-click an album in the side bar and use the command "Download Originals". To be sure, all originals have been downloaded, create an album with all photos and force the download from iCloud this way.

Photos can’t be transferred directly from iCloud to an external hard drive for that you need to set up iCloud photo library see the article Set up and use iCloud Photos - Apple Supporthttps://support.apple.com › en-in

And its preferences Change preferences in Photos on Mac - Apple Supporthttps://support.apple.com › en-in › guide › photos › mac  open finder > Go > home > your user name > pictures either drag and drop Photos Library.photoslibrary to an external hard drive , the second method is right click on Photos Library.photoslibrary and click on show package contents in the upcoming column , you can also drag and drop complete masters folder to an external hard drive that is connected .

Also as per the article Back up the library in Photos on Mac - Apple Supporthttps://support.apple.com › en-in › guide › photos › mac

Manually copy your library to an external storage device: Drag the Photos library (by default in the Pictures folder on your Mac) to your storage device to create a copy.See this article also

Photos library - Move your Library to an external storage device

To sign out from iCloud account you must have iCloud Keychain security code in your records , if you don’t remember it , change iCloud Keychain security code from old one to new one as this code has to be filled up in the upcoming steps .

( a ) Open system preferences > iCloud > the box for keychain is checked , click on options , click on change security code .

( b ) Click on security code > enter new code in the fields and click on next , you have to enter the new code for the second time and click on next .

In the next window the country code is written , enter your trusted mobile number …….and click on done .

Again enter your Apple ID password to update your account settings and click on ok , hence the code is changed , so write down this code in a safe place .

Then follow the article If you sign out of iCloud on Mac - Apple Support