How do I make friends?

My husband is 28 and I’m 23. We’re the only friends each other has. He had a friend group but they moved and grew away from him when he had his first daughter at the age of 22 (my step daughter). We also now have a 1 year old daughter and I’m 5 months pregnant with a baby boy.

It sucks not having interactions with other adults outside of work and my spouse. I work in a small office with individuals who are all 20+ years older than me. My spouse and I love each other’s company but we also love to hang out in a group setting or go on double dates.

How do we make friends? How do I make mom friends?