AutoCAD Drawing Lines

1. Open a new drawing. Click New
2. Open new drawing. Make sure you’re in 2D Drafting & Annotation workspace.

3. Type z [Space bar], type e [Space bar]. This will zoom extents your drawing area.
4. From the ribbon tools, click LINE

5. Specify first point of the line at 0,0. Type 0,0 [Enter]

4. Specify next (last point) at 8,8. Type 8,8 [Enter]. Press [Esc] to end LINE command.

5. Your line is completed.

Your first point of line could be any where, instead of input coordinate (0,0) you can point and click any where as your first point of the line.
For creating continuous line you can continue inputting next points and to end the LINE command just press [Enter] or press [Esc] key.