create table test (
  sr varchar2(1),col1 number,col2 number,col3 number
) ;
insert into test values ('a',1,2,3);
insert into test values ('b',4,5,6);
insert into test values ('c',7,8,9);

Col   A B C
Col1 1 4 7
Col2. 2 5 8
Col2  3 6 9

So you want to flip the rows and columns around, aka a transpose?

You can do this by chaining unpivot and pivot operations.

First an unpivot, to turn the column values into rows:

select * from test
unpivot ( 
  val for col in ( col1, col2, col3 )
);

SR    COL     VAL   
a     COL1         1 
a     COL2         2 
a     COL3         3 
b     COL1         4 
b     COL2         5 
b     COL3         6 
c     COL1         7 
c     COL2         8 
c     COL3         9

Then add a pivot afterwards to create a column for each value for SR:

select * from test
unpivot ( 
  val for col in ( col1, col2, col3 )
)
pivot (
  min ( val ) for sr in (
    'a' A, 'b' B, 'c' C
  )
);

COL    A   B   C   
COL1   1   4   7 
COL2   2   5   8 
COL3   3   6   9 

Read more about this at:

https://blogs.oracle.com/sql/how-to-convert-rows-to-columns-and-back-again-with-sql-aka-pivot-and-unpivot#transpose