1993 buick regeal wont start new battery still

Make sure the cable ends attached to the side terminals of the battery are immaculately cleaned by a wire brush and baking soda and water.

If it still won't start with a new battery, it's likely the starter is bad.

However, you might want to check to see the amperage draw when trying to turn it over with an amp meter (inductive type).

If it draws 75 A or above and doesn't turn over, the starter is bad.
If it draws 0 A and doesn't turn over the starter's solenoid may be
not functioning.

May want to take it to Sears or Walmart to have th starting and charging system checked out.

Good luck.