iCloud Keychain can change all my passwords at one time or no?

iCloud Keychain stores password for wifi , website passwords as explained in the article https://support.apple.com/en-gb/guide/mac-help/mh43699/mac

Including the Apple ID and password that can be changed https://support.apple.com/en-us/HT201355

For other web site passwords you have to wait , let the password changing process of any be completed then change wifi password or other applicable for Mac , in iPhone the passwords are synced by checking the box of keychain .

For you tube account using google see these articles https://support.google.com/youtube/answer/9701986?hl=en

https://support.google.com/youtube/answer/2802848?hl=en

reharv wrote:

iCloud Keychain can change all my passwords at one time or no?

No.

Does it protect me as I have Google with YouTube TV

I don't follow or understand this second question.