in your own words provide two advantages of using meters as a measurement of length rather than old measurements of length such as hands or steps

First, the meters is the unit used in almost all the world today.

Then using meters as your unit will be easier to read and interpret for a larger number of people than if you use an older system, like hands or steps.

And because of the fact that almost all the world uses the meter as the unit for length, almost all the equations and formulas are written in meters.

Precision: The meter is exactly defined as:

"The length of the path traveled by light in a vacuum in 1/299,792,458 of a second"

So the meter is an exact (and accepted) unit.

Then using this unit for measures of length also provides some " legitimacy" for you measure.