Welcome Jefferson!
I would start by listening to this podcast explaining the levels.
On the Dashboard, there’s a tool called “Progress,” which gives a recommended number of lessons at each level. My experience is that it’s quite accurate in telling me how many lessons I should listen to before that level stops challenging me. At that point, you can start exploring the next level up (such as Elementary), while continuing to do more lessons at the lower level (such as Newbie).
John and Jenny explain all this in the podcast.
But I do need to warn you that the difficulty of the levels changed significantly in 2015. The “Dashboard” was designed before that time. If you’re not aware of that, you could easily get discouraged by lessons that are suddenly too easy or too hard. Almost all of the Newbie lessons were produced before 2015, so it shouldn’t affect you too much until later.