Let's say you are planning to update your phone number that has been registred with an organization.
I am not sure this is the number that i want to change to.
I am not sure this is the number that i want to change from.
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Sign up to join this communityThere is only the usual difference between "to" and "from".
"From" is the starting point. "To" is the destination. So "the number I want to change from" is the old number, and "... change to" is the new number.