How i can use blob data type?

[Raminder]

Yes. You can store Images in BLOB datatype in Oracle.
Using it is a bit tricky. You have to use DBMS_LOB package and know the syntax.
First Create an Oracle directory corresponding to the OS directory where your images are stored.

create directory root_dir as 'C:/My_Pictures';

After creating the table with a column of BLOB datatype, you can initialize it by storing empty values (different from NULL values).
Then you can load images with a procedure like this:

CREATE OR REPLACE PROCEDURE loadLOB_proc IS
   Dest_loc       BLOB;
   Src_loc        BFILE := BFILENAME('ROOT_DIR', 'ocp_logo.gif');
   Amount         INTEGER := 4000;--this can be as per size of image
BEGIN
   SELECT image INTO Dest_loc FROM imagetest
      WHERE ID = 1 FOR UPDATE;
   /* Opening the LOB is mandatory: */
    DBMS_LOB.OPEN(Src_loc);
     /* Opening the LOB is optional: */
   DBMS_LOB.OPEN(Dest_loc);
   DBMS_LOB.LOADFROMFILE(Dest_loc, Src_loc, Amount);
   /* Closing the LOB is mandatory if you have opened it: */
   DBMS_LOB.CLOSE(Dest_loc);
   DBMS_LOB.CLOSE(Src_loc);
   COMMIT;
END;
/
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Wish you all the best.