@TeenGirl2024 please read some of the things people are saying here, and have a big think about them.
Firstly, you are very young, and as far as I can tell this was not a planned pregnancy and I don’t think you are married either are you? You were engaged and living with your fiancé’s family when you first found out you were pregnant but I don’t know if you have married since then. This puts you in a position of uneven power in the relationship to begin with. If you are not actually yet married, but have had a baby with a man, you could be left in financial trouble if he decides to split with you or even if he dies (he’s young, but marriage includes legal protection for a spouse in many ways.) The fact that you have been living with his family rings alarm bells for me too. This puts you in a vulnerable position.
On to the finances - in a normal relationship where two people live together they sit down, talk about the household income (from both parties) and outgoings, and work out how they will pay the normal household bills. There are a lot of ways to do this, but the usual way is for each party to be paid into their own bank account and each transfer a sum by direct debit each month just after payday into the joint account and this is the account that pays for bills, groceries, child related stuff, etc. In our household, the amount paid into this joint account is not equal, because I work part time and stayed home to look after the children when they were little, meaning my career did not advance as much as his did. So now he puts more in the joint account than I do. Then we each have what is left in our own accounts to spend as we like. On a regular basis we sit down and look at what our costs are, have any gone up (cost of groceries) or down (no longer need babysitters) and also look at our income - did anyone get a pay rise or bonus or is one of us out of work for any reason? And work out if we need to adjust the amount we put into the joint account. The joint account never runs dry. It pays for our essentials like food, heating, a place to live. Our own accounts can and have run dry, and this means we have to work harder or cut back on hobbies or other personal spending. We don’t get to have the fun stuff without making sure the joint account is managing.
In a normal relationship this is discussed and agreed from the moment you move in together. And then adjusted regularly to account for changing circumstances such as pregnancy and maternity leave. If one person is putting themselves in debt because the other won’t pay, or if one person is afraid to bring up money matters because of the way the other will react, then it is not a normal relationship. It is a financially abusive one, or on its way to becoming financially abusive.
As your baby grows, it will cost more in the way of food, clothing, child care, etc. Please speak with your husband - first of all, protect yourself and your child by making sure he actually is your husband. Secondly, have an adult conversation about finances. He is still very young too at 25, and it may be that he has no idea how normal relationships work if his family are as dysfunctional as you imply. If you absolutely cannot speak to him about this at all, you are looking at a future of either financial abuse or a future bringing your child up on your own. If he is the ‘lovely man’ you say he is you need to get these things sorted out sooner rather than later.