La Ti Do Re Mi
This is a melody from one of the very famous singing training book "Fifty Lessons for the Voice" by Giuseppe Concone.
Listen to the first movie and then go to the second one. You can practice tis melody phrase by phrase with that.
You don't have to care about the "Do-Re-Mi" so far, Just try to sing with "la-la-la" or any kind of vowels.
Could you recognize this melody is starting with Do-Re-Mi-Fa-So, then move up to La-Ti-Do-Re-Mi?