Reading The Three Columns
The 0% column is the plain sum: what is still missing, divided by the months you have. It is the amount that gets you there even if your savings earn nothing.
The other two columns show how much less you would need to save each month if the money grew at the rates you entered. For goals a few years away the difference is usually small, because there is little time for growth to build. For long goals it becomes large.
A higher assumed rate lowers the monthly figure on paper, but it normally comes with more risk of falling short. For money you need on a fixed date, many people plan around the lower figures.