You can overload program units by using different names of parameters as long as you use named notation when you call the program units.
SQL>
SQL> declare
2 function getArea(i_rad NUMBER, i_prec NUMBER)
3 return NUMBER
4 is
5 v_pi NUMBER:=3.14;
6 begin
7 return trunc(v_pi * (i_rad ** 2),i_prec);
8 end;
9 function getArea(i_length NUMBER, i_width NUMBER)
10 return NUMBER
11 is
12 begin
13 return i_length * i_width;
14 end;
15 begin
16 DBMS_OUTPUT.put_line('Area (R=3): '||getArea(i_rad=>3,i_prec=>1));
17 DBMS_OUTPUT.put_line('Area (2x3): '||getArea(i_length=>2,i_width=>3));
18 end;
19 /
Area (R=3): 28.2
Area (2x3): 6
PL/SQL procedure successfully completed.