Very sorry to learn that you are having cancer with diffuse distant metastasis to different sites.
Ideally there are three types of treatment for any cancer and this involves surgical removal,radiotherapy and chemotherapy
.Since surgery and radiotherapy can not be done in your stage,treatment left for you would be only chemotherapy as suggested by your doctor.
As far as prognosis for you is concerned,it is definitely not very good and one definitely doesn't get many years.
But if you resort to chemotherapy,then thete are chances that you may get few years and during tjis time you can plan for your dear child.
In my opinion you should fight it out with chemotherapy and positive mindset and gain as much time as it is possible since there are various new chemotherapy agents available which can make you gain enough time.
I know it is hard for you but there is no way backward and so you have to move ahead with positive mental approach.
Best of luck to you and god bless you and your daughter.