As a teacher I always emphasize the importance of knowing your scales. Too often there is so much concern over learning the repertoire that a lot students only gloss over knowing anything about scales. Even beginner cello players can learn to play scales. Remember learning scales may be not as exciting as a song, but it will really show you where notes are on your cello and help you become more familiar with the fingerboard geography.
In this video I talk about the C major, G major, D major, and A major scales that you can play while you are in 1st position. There are definitely extensions involved, but if you remember that you don’t move your hand, you just stretch AND that your thumb should stay under your middle finger at all times you should do just fine.
Remember all things get better with more practice and scales should be part of your daily practice! Let me know if you have any questions and be on the lookout for another video covering scales using flats.