There is a “Start Here” forum category…
As a seasoned developer, my recommendation as an avid observer is to work your way through the very-much-in-development Holochain Gym and follow the Holochain in Action series.
The Holochain Gym is essential not to skip as development has significant differences to consider when developing distributed, decentralised apps, and having been watching the Holochain in Action YouTube session videos that is very helpful to see how to build a useful app.
Of course it’s always helpful to note things you notice on your journey and post recommendations for changes in order to help the next person visiting and not discovering where to start. I try to do my bit in the areas I’m interested in - the official team are always mega-busy building the actual thing so anything we can do to help alleviate pressure and improve the surrounding supporting material brings us closer to awesomeness arriving!!!