Boyfriend wants a baby but is scared HELP

My boyfriend of 14 years and I want to have a baby so badly but he says I want a baby but I'm worried what if things change with us but he always talk about how we are going to raise them how do I reassure him im24 he's 24 in March and sometimes he says I'm only 23 I'm confused it something we both truely want but of course there is going to be concerns help please