Dear OP, please don’t take this negatively, but you are still very young, and I say that as someone who had a child when younger than you are now. I can only speak from my own experience to say that if you can delay having a child for a few more years you will have so much more to offer your baby. Having a child as a young woman really puts a lot of limits on you in so many ways. In no particular order.
career wise : having a young child (or children if you do them back to back) really slows down a woman’s career progression, yes, you can make it up, but it is hard, limiting your hours due to childcare, losing out on training, promotion, travelling, flexibility of location can all really impact your working life. It is also so much easier to do things like professional qualifications and /or university when you are child free. Which leads on to
finance: all sorts of problems here, some from not being in a job which offers good maternity benefits, from wanting to stay at home and finding smp barely pays the rent(while it lasts) ,from making sure you keep your pension pot healthy , to finding yourself being dependent on someone else’s income, which leads on to
relationships: your partner has already made his views clear. A not 100% wanted pregnancy and baby can put huge strains on a not fully committed relationship, especially one which is fairly recent . If he sticks around make sure you get some security in communal property by getting married, but also be prepared to spend the next 18 years trying to get financial support for a child if he decides he isn’t ready for fatherhood.
My last point is about you as a person, you don’t sound as though you have had that much experience of life, it is amazing how much you grow and change during your 20 s, your ideas change, your interests, if you have a decent income and no ties you can travel, entertain, indulge yourself in your hobbies and whims, which means that when you do eventually have children you are a more settled, rounded, interesting , mature person who has so much more to offer a child.