When branching out from the basics of bedside ultrasound having a standardised approach helps improve your technique and train your brain to recognise abnormalities in the images you see.
There are standardised approaches developed by ITU docs for thoracic scanning but these are comprehensive assessments rather than the focused imaging designed to answer a specific clinical question.
BelowJacob Avila of Ultrasound Podcast and 5minSono shares his approach for ED Thoracic US, which seems like a good place to start.
Go to his wesbite for loads of other good teaching on ED US: 5minsono.com
Heres some other great Thoracic US videos for you to get your eye in.... then give it a try!