how to make entry in a table e.g. vbak table
how make entries in a table.
what is the procedure.
can i do it in production directly?
Its always better to use some standad SAP procedure to make an entry into database table like BAPI , BDC etc.
You cannot do directly on to production server its not at all a good practice.
If yours is ztable then possible through either maintenance view or by program having INSERT , UPDATE, MODIFY statements.