These days, yes.
Really, that depends on what you want to do.
DIY is much cheaper, and there are guides to make the process easier to go though, you do need the each individual parts though.
Pre-Builts are just much easier to set up (cause all you do is just plug it in), but a bit costly. Though you can swap out of a part later on if you wish.
While i never personally built a computer, i have swapped parts before and it’s surprisingly simple to do, so i would imagine building a computer is that simple, and hence, that’s my advice right there. 
Again, Heavily dependent on you want.