The FAA has two excellent books that are a great start to your flight training.
1. The FAA WEIGHT-SHIFT CONTROL AIRCRAFT FLYING HANDBOOK. Download it for free here:
2. The FAA Seaplane Handbook. Even though this book is about flying airplanes from the water and doesn’t mention trikes specifically, it is still a must-read. Read it to understand the principles of water flying to apply to your trike flying. Download the FAA Seaplane Handbook here: