Baby food

Mariah • Nerd. MCU <3
So I'm breastfeeding and planning a cruise, and a camping trip. Both of which little one will have to stay with his grandparents. It's going to be a long time from now. How old does baby have to be before eating baby food?? I want to breastfeed too. But I don't think I'll be able to save up enough milk for the long trips. So a good mix is what I'm thinking.