AutoCAD is not an intuitive CAD program, and gave me grief learning it by myself back around rev 3. [Rev numbers went to 12 or 14, then started using years, I think in 2000].
To draw, you need to click the icon for what you want to draw [line, arc, circle, etc.]. Then select a starting point [which is often the center of a circle or arc], then move the mouse and select the desired end point.
Drawings will look better if you don't try to visually attach lines to each other, that's what the Snap function is for. Important toolbars are Draw and Modify. There's a whole slew of icons that will start your next line/arc/circle at various points already drawn--the end of a line, the center of a line, the center of a circle are the ones I use most often.
Sorry, this is from memory, just bought this computer two weeks ago and haven't moved my ancient home version of ACAD onto it yet, and the new job I started the week before that doesn't use it, just SolidWorks, and it's much more complex and much more capable.
Good luck, and happy drawing! Try not to get too frustrated, just remember it's not very intuitive. For scale drawing, it is even less so.
LAYER is a handy command, so that you don't get too confused. Make each layer a different color to keep things separated in your mind. Each layer can be turned off for clarity. ZOOM is very helpful to spot things or select the right point; ZOOM PREVIOUS will take you back without losing the selection, which is what UNDO does.
HINTS:
- Construction lines are of infinite length; learn to use Offset [then enter the desired distance] and draw another line. A third line crosses these two, then use Trim to cut the line to length and erase the construction lines. Voila! A line of desired scale length
- To draw an angled, click on your starting point and use polar coordinates [formatted @.625<30 will draw a line 0.625" long with the right end elevated at an angle of 30º above horizontal].
- Or draw a straight line, click Rotate, select the line, click one end [snap to end works well], then either drag the other end around or enter the angle. Positive angles rotate counterclockwise [right end up]; negative angles rotate clockwise [right end down].
- OFFSET, TRIM and STRETCH are wonderful things!