Hi Himanshu,
It depends what object types these fields are on. . . .
If you have the same field on different forms, but on the same object (i.e., two forms on the same project. The forms have the same field on each), then populating one field will automatically populate the second field with the same information.
If the fields are on different objects in the system, this can be achieved by ensuring that the field exists on a parent object and then using calculated fields to reference the value of the parent object. I.e. if Field 1 has a value of "A" on a program, you could create a calculated field to pull in this value on all projects within that program: {program}.{DE:Field 1}
Another option is to use Fusion to automate the population of these fields.
Hope that helps.
Best Regards,
Rich.