My right to work during waiting time

I have applied for ILR and submitted my biometric on 23rd September 2019. The decision is still awaiting. My present visa status which is dependent is expired on 19th October 2019.

I am a Bangladeshi citizen and my spouse is a British citizen.

what are my rights to work and present immigration status?

I am supposed to join to a new job soon. What documents shall I present them to prove my rights to work in UK.

what are my rights to work and present immigration status?

As you applied before visa expiry, your previous visa conditions continue under Section 3C of the immigration rules while HO processes your application

I am supposed to join to a new job soon. What documents shall I present them to prove my rights to work in UK.

Unfortunately without a valid visa or ilr brp as evidence, you likely won't be able to start as you don't have anything physical to prove your right to work.