in skeletal formulas each end of a line represents a carbon atom.
1- as we are drawing "prop"anol then we have to draw 2 lines, each end representing a carbon.
2- as we are drawing 2-bromo we have to draw a vertical line with Br at its end at the 2nd carbon.
3- as we are drawing 2-methyl we have to draw another vertical line at the 2nd carbon with CH3 at its end .
see the attachment.