Finally pregnant after having miscarriage

Me and my boyfriend have not really been trying but ‘if it happens it happens’ don’t want to get to focused with it at one point in the first few months I was trying everything even lying with My legs in the air... anyway

Today I found out I am pregnant ... now my boyfriend suddenly has a change of heart and is demanding I get an abortion, I love him with all my heart and I feel like my relationship is on the line but I cannot abort my child after having a miscarriage I just can’t do It I feel so blessed to be able to have a second chance of having a baby and he’s just not happy in the slightest I’m 21 and I’m scared of the outcome? How am I meant to be happy when he doesn’t want it, how am I meant to go about telling my family about my pregnancy and how the love of my life is making me choose between him or my baby