One issue — not limited to iNat, but true for everything — is that you learn by doing.
In other words, you could create the best iNat intro program in the world. The best one ever created. There are many resources on this forum that will help you do that.
But the only way to truly learn is to use the platform for years. If you read the forum, you will find many comments from people who used iNat extensively for years, only to learn some shortcut that massively increased their workflow.
Once you know it, it seems obvious, and it is mind-boggling to you that you functioned for years without knowing it.
Learning by doing and making mistakes.