Some Lines Not Visible And Cannot Copy and Paste
1. It makes little sense to break out such a simple sketch into 4 different sketches.
2. When you are copying, you have to start a new sketch into which you can paste all these elements.
I am not sure what you intend to accomplish by that.
That is difficult to answer without having access to your file.
However, I see these chained lines you describe. They are simply a different color (purple).
But, again, it does not make a lot off sense to me to make 4 separate sketches for something that simple.
If you can post a sketch (perhaps on paper wit pencil) or an image of what you are trying to design it would probably best.
With all due respect, your training exercises are aimless without a distinct goal.
I stand by what I said, making 4 sketches and copying and projecting stuff between them is not going to get you anywhere.
The purpose of most sketches is to create 3D geometry. You have 130+ posts and are still stuck drawing sketches.
Pick an object that you want to replicate and with that in mind you need to start learning.
Drawing arbitrary shapes in sketches and copying stuff between sketches is not going to get you anywhere. You'll be stuck forever drawing sketches!
No, you don't!
You appear to be afraid to make a mistake to the point of paralysis . You need to move past that. I re-resiged my first design in Fusion 360 three times from scratch so I could get the correct workflow down. I made mistakes. In times it was frustrating. But I did move on and learn.
You cannot see the consequences of what you are sketching in the 3D object if you don't move past basic sketches. Some understanding will simply come by trying lots of things. Unless you have a hard deadline for submitting a design, making mistakes in a CAD design is fast and easy. Cherish the mistake. The more you'll make, the more you'll learn 😉