Using the official build allows you to learn the software exactly as it's used in professional studios. How to Download Old Versions (Like Houdini 19)

The Houdini Launcher makes it easy to install and manage multiple versions of the software on one machine. Final Recommendation

You won’t have access to the SideFX Support team or official updates to fix bugs. The Better Way: Use Houdini Apprentice for Free

You get access to nearly all the features of the professional version, including advanced nodes for modeling, animation, and simulation.