Hold on a minute. If carnation instant breakfast has good quality nutrition (I do not know if it does ), but if so,why would it not be a good meal replacement.
It is easy for anyone to say you have to learn balance,blah blah but if I recall correctly, consumer reports said meal replacements were a very good adjunct to weight loss.
If some pounds are lost, then it would be motivating to go into the balanced meal approach. Don't knock anyones attempt to try an alternative approach to at least make a start.
The plan would not be to my liking but good luck with your efforts.