Thank you all for reply.

Let me answer stylish point one by one and hope it will answers others too.

1. I haven't stamped my H1B. It just got approved and I have approval document for USCIS

2. I won't be there for stamping. I will be here and my spouse will go for interview at KTM (US embassy)

Now My question is I am doing job since last 2 years but I got new job offer letter with increase salary in this march (for H1-B process), Do I have to send that new job offer letter too?

What are other consequences we have to consider for H4 VISA?

Thank you all for quick response.