Q: I changed my applied password through iPhone, and I have a separate password at the Macair. Each time I signin macair it asks me local items keychain password

Please sign out of iCloud in its preference pane and see whether there's any change. No data will be removed from the servers, and you can retrieve it by signing back in. That said, you should always have a current archive of the data for safety's sake, even if you don't sign out.

If you use iCloud Keychain, when you sign back in to iCloud follow one of the procedures described in this support article to set it up on an additional device.