Cant put Audible books in iPod nano

I just got some books from audible with the idea that I would put them on my iPod nano so I can listen to them in the middle of the night. But apparently with Catalina, books are not in music anymore and books won't let me transfer to my ipod. I have serious insomnia and this is the only thing that works for me. I don't have Wi-Fi at home and my computer doesn't come to my bed and I already have too much stuff on my phone so I can't put them there. Anyone got a miracle for me?