TrueNAS is not as simple as videos make it look, though it is fairly easy to get a system running if you read the documentation and don't color outside the lines.

If you want to save yourself lots of money and loads of time, the top of the page has Documentation and Resources tabs which contain extremely helpful information like the TrueNAS manuals. There's also a Search tool at the upper-right that works extremely well. If you understand the system and requirements before jumping in you'll save money, time, and frustration.

As general advice, if you run TrueNAS as a NAS and don't add things to it it tends to run fine and without issue, though I suggest using an Uninterruptible Power Supply and NUT.