Universal credit and satm split finances

Hi all,

I want to work but we haven’t yet completed our family and he works however is on low income

So I wondered whether it’s fair to help him by getting in discussion as to where the money should go or I do my own thing via helping through purchasing for home, food and baby

Because I’m very independent and I want to choose items myself for baby and etc whereas when I work I’ll likely do same

But he seems to be losing it, and calling unnecessary spending