Growing bonsai from seed is an extremely rewarding experience. The hard part is finding information on how to start and nurture seedlings. There are many resources available online, including numerous videos demonstrating how to apply moss to bonsai trees. One great resource is the Bonsai Empire. This site contains tons of information, from how to develop seedlings to how to care for your bonsai trees.
Another great source for learning how to grow bonsai is the Eisei-en online learning platform. This platform offers free tutorials from two well-known bonsai artists and includes two videos a month as well as regular live Q&A sessions. You can also learn from Peter Chan, a British bonsai artist with an expansive bonsai nursery in England. His videos emphasize beginner-friendly techniques.