I want to create pivot table or cross tab for POSTGRESQL. Any help would be appreciated

Doing so is ridiculously hard.

CREATE TABLE datatype(id serial , code text);
INSERT INTO datatype
SELECT  r,format('Q_%s' ,r)
FROM generate_series(1, 10) r;

CREATE TABLE model (id serial , dtid serial , value numeric , exid serial);
INSERT INTO model
SELECT  unnest(ARRAY[1,2 ,3,4 ,5])
       ,unnest(ARRAY[10,8 ,9,1 ,2])
       ,unnest(ARRAY[0.001,0.008,0.1,0.9,0.6])
       ,unnest(ARRAY[1,1 ,4,3 ,2]);

CREATE EXTENSION crosstab;

SELECT  *
FROM crosstab
( $x$
    WITH a AS
    (
        SELECT  exid, dt.id, dt.code ,SUM(value)
        FROM datatype dt
        JOIN model m
        ON m.dtid = dt.id
        GROUP BY 1,2,3
        ORDER BY 1,2
    ) , b AS
    (
        SELECT  exid
        FROM a
        GROUP BY  1
    )
    SELECT  b.exid, dt.code, coalesce(a.sum, 0)
    FROM b
    JOIN datatype dt
    ON true
    LEFT JOIN a
    ON a.exid = b.exid AND a.id = dt.id
    ORDER BY 1, 2$x$
) AS (exid serial , q1 numeric , q2 numeric , q3 numeric , q4 numeric , q5 numeric , q6 numeric , q7 numeric , q8 numeric , q9 numeric , q10 numeric );

Be warned, you have to put together the end of the query (result type) in program. If it would be psql, then it wolud look like this:

SELECT format(
        $omfg$
        SELECT * FROM crosstab(
                $x$WITH a as (
                    select exid,
                        dt.id,
                        dt.code,
                        sum(value)
                    FROM datatype dt
                        JOIN model m ON m.dtid = dt.id
                    group by 1,2,3
                    order by 1,2
                ),
                b as (
                    SELECT exid
                    FROM a
                    GROUP BY 1
                )
                SELECT b.exid,
                    dt.code,
                    coalesce(a.sum, 0)
                FROM b
                    JOIN datatype dt ON true
                    LEFT JOIN a ON a.exid = b.exid
                    AND a.id = dt.id
                order by 1,2 $x$
            ) as (exid serial, %s) $omfg$,
            (
                SELECT array_to_string(array_agg(code || ' numeric'), ', ')
                FROM (
                        SELECT code
                        FROM datatype
                        order by id
                    ) c
            )
    )  gexec

Before you try to understand the code above, you should read the docs about the crosstab function here: https://www.postgresql.org/docs/11/tablefunc.html (or from the docs of the appropriate PG version)

You may notice the coalesce(a.sum,0) instead of a.sum in first version. In most cases nicer to use coalesce, but in the question was some n-s in the table, they probably means NULL, without the coalesce you can have them (obviously).