Most babies are ready to start solid foods as early as 4 months of age however some babies may not be ready until 6 to 8 months of age.
As soon as your baby is ready to start solid foods which is between 4 and 6 months of age then you can puree some butternut squash so your baby can eat it.
You can do that with a lot of vegetables and make your own organic homemade baby food like my mom did for me when I was a baby.
My mom never bought in store baby food for me and she just made my baby food at home using her blender and regular vegetables.