Will I qualify for head of household?

I will be having a kid at the end of the year. I am single, but live with my partner who will be adopting the baby. Currently, we basically split bills/food 50/50 the only thing is I probably pay for more utilities. The kid will be going on my insurance.

I’m just try to get an idea of how I should/could file for this year. I would have less of a tax burden by filing HOH, but I’m not sure how it works exactly with the 50% of expenses situation.