How can I upload my pictures to icloud

Here are links that will provide guidance:

Keep your photos safely stored and up to date on all of your devices - iCloud Photo Library - https://support.apple.com/HT201313

Set up and use iCloud Photos - https://support.apple.com/HT204264 - FAQ

Use iCloud Photos to store photos in iCloud

https://support.apple.com/guide/photos/from-icloud-photos-phtf5e48489c/mac