Hi 1parkerj1,
welcome to the Apple (user-to-user) Community.
Re: How can I make sure all of my pictures and videos are safe if I stop using Icloud. Should I save all of them to my computer (windows10) or are they okay in google photos? I am terrified of losing anything
Am no expert in this area, yet your question surely deserves a response.
As I do not use a PC, or google photos myself, I can not say how secure, or safe, your files will be there.
Seems many of us keep a back-up copy of all our photos and videos on an external hard drive we buy.
Also, Apple does suggest we keep a copy of all the information we store in iCloud, google may also, or may not.
Apple support have an article online (link below) that may help you keep your photos and videos safe yourself.
See how to: Archive or make copies of the information you store in iCloud - Apple Support
Eg: says:
"Download copies of your photos and videos from your device
On your PC, make sure you've set up iCloud for Windows
Open File Explorer. In the Navigation pane, click iCloud Photos, then select the images you want to keep on your PC. Right-click the selection and choose "Always keep on this device".
If you use iCloud for Windows 10 or earlier, find out how to download your photos.
After the items have been downloaded, copy them to another folder on your computer. To do this, press and hold the Ctrl key and drag the items to the folder. Include this folder if you back up your computer."
NB: It is not difficult to copy the photos and videos to an external drive, if you wish.
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Seems ICloud is a syncing service.
If you just delete files from either iCloud or PC, the files delete from both places in order to keep in sync. for you. If needed: recently deleted photos and videos can be recovered for up to 30 days. However if you permanently delete a file from the Recently Deleted folder, you can’t recover those photos or videos.
How to: View, add, or remove iCloud Drive files in iCloud for Windows - Apple Support
Eg: also says how to:
Move items to your Windows computer and remove them from iCloud Drive
- On your Windows computer, open File Explorer or Windows Explorer, then click iCloud Drive in the Navigation pane.
- Locate the items you want to remove.
- Drag the items from iCloud Drive to the desktop or another folder on your hard disk.
- The items are moved to your Windows computer and removed from iCloud Drive on all your devices that have iCloud Drive turned on. If you change your mind, you can drag the items back to iCloud Drive.
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If you wish: You can cancel iCloud+ in your iCloud storage settings.
How to: Downgrade or cancel your iCloud+ plan - Apple Support
All the best :-)