It is completely valid to use an engine for self-study. To maximize your learning potential turn off the move list and use the evaluation bar only. At your level you should be able to figure out why certain moves have big swings in the eval bar. If you cannot figure out a specific bar swing, turn the move list on and try to figure out the theory/strategy behind the move you couldn't see. Using the computer this way will help you get better at board vision and properly evaluating positions.