Cut it into equal parts: halves and quarters.

Two friends share one roti. They cut it into 2 equal parts. Each friend gets one half.
A whole cut into 2 equal parts makes halves. One part is one half. We write ½. Two halves make one whole.
Cut a whole into 4 equal parts. Each part is a quarter, ¼. Four quarters make one whole. Two quarters make one half.
Fractions must have equal parts. If the parts are different sizes, they are not halves or quarters. A quarter is smaller than a half.
Cut a roti into 4 equal parts. Eat 3 parts. You ate three quarters: ¾. Two quarters make one half, and four quarters make one whole.