I can't replace a digit form a 10 or 14th digit number ?

SUBSTRING-function should be your friend here.

UPDATE tbl 
  SET ID = SUBSTRING(ID,1,11) + '3' + SUBSTRING(ID,13,2)
WHERE
  SUBSTRING(ID,12,1)='2'

But keep in mind that the above query won't be able to make any good use of indexes, since the WHERE-clause uses a function on the index. And since you are interested in the value of the 12th digit in a a string, no other comparison method will be able to make use of indexes either. I'm guessing your table has ID as a clustered primary key, and then the above query will result in a table scan. For a small table, that might not cause too much pain, with a large table, your server will be kept quite busy scanning the table and moving pages in and out of memory.