Once they are in your iCloud account, they will sync with all your devices/computer sycing contacts with your iCloud account.
Also, the contacts you copy to your iCloud will not sync with your exchange account. If any changes occur in your exchange account contacts you will have to manually make these changes in your iCloud account. If, for example, a new contact was added to your exchange account, you would have to manually add this to your iCloud account. It wouldn't be added automatically as iCloud cannot sync with external account.
If you still want to copy your exchange contacts to iCloud, do the following:
- Go to Settings>iCloud, turn Contacts to Off, choose Delete from My iDevice when prompted (any iCloud contacts will still be in iCloud).
- Download the app My Contacts Backup. (If you have more than 500 contacts to transfer from your exchange account you will need the “Pro” version. If you aren't sure, start with the free app. It will tell you if you have more than 500 contact when you use it.) Use the app to back up the remaining contacts on your phone (from your exchange account) as a vCard attachment to an email that you send to yourself. Confirm that you have received the email.
- Go to Settings>iCloud and turn Contacts back to On.
- Go to Settings>Mail,Contacts,Calendars>Default Account (in the Contacts section) and set this to iCloud.
- Go to Settings>Mail,Contacts,Calendars…tap your exchange account and turn off contacts syncing with with your exchange account (otherwise you will see duplicate contacts on your device).*
- Open the My Contacts Backup email and tap the attachment to import the exchange account contacts back to your phone, and to iCloud. All your contacts should now be in iCloud, and appear on icloud.com and your other devices/computers.
* If you don't want to turn off contact syncing with your exchange acocunt, you will need to open the contacts app and tap Groups, then tap the exchange account so it is unchecked. This will hide them from view so you don't see duplicate contacts on your phone.
