I am rather new to all of this, thanks for those who have replied already. I have added more information at the end of the post to show how far I have got. What I would like to be able to do is pinpoint his death and see if I have bought the right certificate. Then I want to see why and how the family dispersed.
Dear All, I have hit a dead end with my Great Grandfather, James Miller. In 1901 he was living with his wife, Catha(e)rine and their children, including my grandfather Anthony and twin 1 month old daughters, Rose and Lillie. In 1911 the whole family was dispersed and his wife was in the workhouse and Anthony was in another in Fazakerley. The twins died in 1901. Can anyone please help me to sort out this mess?

I bought the death certificate of a James Miller, but now I am not sure it is him. My GF joined the merchant navy when he was way underage, he lied about his age. Eventually he became a doorman at the Adelphi and committed suicide in 1958. A very troubled man, but hardly surprising given his start in life.
Marriage 15th November 1893 in All Hallows church Allerton, Liverpool. Age 31, living in West Derby, father James Miller (deceased) to Catherine Jones, living in Allerton, father John Jones (deceased)
1901 Census James Miller 41
Catherine Miller 37
Margaret Miller 6
Anthony Miller 4
Helen G Miller 3
Lily Miller 1/12
Rose Miller 1/12
1911 census Catherine Miller Walton on the Hill, Lancashire, England, Marital Status: Widowed; Relation to Head of House: Inmate. I found the death of the twins, Rose Miller
Estimated Birth Year
abt 1901
Registration Year
1901
Registration Quarter
Apr-May-Jun
Age at Death
0
Registration district
West Derby
Parishes for this Registration District
West Derby
Inferred County
Lancashire
Volume
8b
Page
387