The Pen Tool refuses to draw lines....like a normal pen would be expected to

As Photoshop yet marches on to go against intuition, the "pen" tool refuses to "pen" for whatever reason it claims that I am doing something it's unhappy about.

So i have a rought drafted drawing on paper (physical paper) that I scanned and imported to photoshop, and intended to trace it with more consistent and straighter/better lines.

Hoped this was simple enough.

Draw with a pen and smooth out curves...

However, I've seen tutorials on YouTube and the "pen" tool apparently keeps tracing something called a "path" and as below, my tracing is highlighted in blue (it's crudely done to show the issue I am facing) if you can hopefully see it;

which, when I press "enter" to commit to the lines created, voila, it disappears. Deletes the lines. So much for the tracing work I've done.

Unlike the "brush" tool, which is just as the same as using a physicial paper and pen (so what's the point using Photoshop if it's no different to errors and minute inconsistencies due to it drawn purely by human hand), I was expeting the pen tool to be smart enough to smooth out slight inconsistencies in lines and curves.

Seems all it does is draw out a "path" and kill it and kick me back to square one when i press enter.

what's the point of this tool??? I tried "shape" but then what it does is fill the entire edges with a colour.

Now, what do I have to give to get a simple tool, very, very simple, that would let me "trace" a picture?

(The Pixel otption, I thought might be what I am looking for but of course, it's inactive because Photoshop has some another random gripe with whatever I am doing - layer? The tool? the picture? No clue)

Why does this only create a path and simply disappers when I commit? Does enter mean delete in Photoshop??? I am extremely confused. 

Why can't I just...draw? Is that so much to ask and does it need to be so complicated?

I'm sorry, every single step I hope it would be simple and basic enough is just extremely complicated in Photoshop and it's getting on my nerves.

It's like being told to use calculus to solve 2+2=?, when I'd hoped my basic knowledge of summation would suffice - evidently, I need to be in advanced math class to solve even something very routine and common in this world.