SQL> 
SQL> WITH DATA AS (SELECT 'One F''ive,Two,Three' a FROM dual
  2                UNION ALL
  3                SELECT 'Singapore ,New York , Ind''ia' a FROM dual
  4               )
  5  SELECT a, REPLACE(a, '''', '''''') conv_a, REPLACE(a, CHR(39), CHR(39)||CHR(39)) conv2_a
  6  FROM DATA;
 
A                            CONV_A                            CONV2_A
---------------------------- --------------------------------- --------------------------------
One F'ive,Two,Three          One F''ive,Two,Three              One F''ive,Two,Three
Singapore ,New York , Ind'ia Singapore ,New York , Ind''ia     Singapore ,New York , Ind''ia

SQL> with data as(
  2  select q'['Singapore , New York, Ind'ia']' a from dual union all
  3  select q'['One F'ive, Two ,Three']'  from dual)
  4  SELECT A,
  5  REPLACE(REPLACE(REPLACE(A, '''', ''''''), ' ,',','),', ',',') conv_a,
  6  REPLACE(REPLACE(REPLACE(A, CHR(39), CHR(39)||CHR(39)), ' ,',','),', ',',') conv2_a
  7  FROM DATA
  8  /

A                                             CONV_A                                        CONV2_A
--------------------------------------------- --------------------------------------------- ---------------------------------------------
'Singapore , New York, Ind'ia'                ''Singapore,New York,Ind''ia''                ''Singapore,New York,Ind''ia''
'One F'ive, Two ,Three'                       ''One F''ive,Two,Three''                      ''One F''ive,Two,Three''

SQL>