How do I access my iCloud email, besides the apple website?

Configure the iCloud mail address with mail application of Mac https://support.apple.com/en-in/guide/mail/mail35803/mac

All the iCloud mails will be viewed in apple mail application , a second way to access the mails is sign in with same Apple ID and password on other devices like iPhone / iPad and turn on mail box in them https://support.apple.com/en-in/guide/icloud/mmb1de40d9/icloud