Slow iCloud set up

See the article Set up your MacBook Pro - Apple Support

If you are signing with old Apple ID , you have to set up iCloud , turn on all iCloud features , set up iCloud Keychain , join the secured network initially , and the data will sync the setting is time consuming it can take more than a hour even your typing is fast on the keyboard , network speed is also one of the factor , a slight incorrect mistake of entering data might stop the settings so use correct procedure .

See some articles Recommended settings for Wi-Fi routers and access points – Apple Support

Set up iCloud on your Mac - Apple Support

Set up iCloud on all your devices - Apple Support

Set up iCloud Drive - Apple Support

The iCloud Keychain has to be set up Set up iCloud Keychain - Apple Support

The photos are to be set up Set up and use iCloud Photos - Apple Support

Change preferences in Photos on Mac - Apple Support

System Photo Library overview for Photos on Mac - Apple Support

The other application mail has to be configured Add email accounts in Mail on Mac - Apple Support

Add an email account to Mail on your Mac - Apple Support

The other applications notes Add or remove accounts in Notes on Mac - Apple Support , calendars Add or delete calendar accounts on Mac - Apple Support

reminders Use reminders from your Internet accounts on Mac - Apple Support

Find my Mac Set up Find My on Mac - Apple Support

The box of Siri has to be checked , in Mac system preferences , it's a time consuming process .