Struggling with the unknown

Hi everyone.

This is my first post here, although I've been reading the posts for a while and found them helpful.

My stepdad was diagnosed with stage 4 lung cancer in July. He had 2 radiotherapy sessions and then started chemo. He struggled with tiredness with the chemo. Then had a reaction after one session which resulted in an over night stay in hospital. X-rays and CT scans showed the cancer had shrunk, which my mum and sister we're all happy about.

It seems like after the positive news everything went downhill. The treatment was paused for him to have a blood transfusion and then delayed again when he was too weak. He had another CT scan and and an appointment was made for him to discuss immunotherapy.

With covid19, he had to attend appointments alone. I would usually go with him. I was good at remembering what the Dr said etc.

Long story short, he came out of his last appointment and said he was told the chemo hasn't worked. The initial shrinking of the cancer was due to radiotherapy but that the chemo seemingly aggravated the cancer which is aggressive and it's spread and immunotherapy was no longer an option.  He said he was told (we don't know if he asked) that he had around 2 months to live. He was prescribed 6 weeks of steroids (he always felt better on them- had an appetite etc) he has now been passed on to the palliative care team.

The steroids don't seem to be working. He has very little appetite or energy. He seems 'slow' mentally. Stares off into the distance a lot. Is quite snappy and verbally aggressive with mum.

He is scared of covid19 so him and mum are spending Christmas alone. We're all so worried and scared for him. Looking online (not a great idea , I know) he is displaying signs of end of life. 

We feel unsure of how to handle everything. He seems to have shutdown and it already seems like part of him is gone.

I don't actually know what I am asking. Are the dr's prognosis' usually accurate? Are there any surefire signs of which will make us know 'this is it?'. What can we do to help him? We feel so useless.

Thank you