The link below takes you to a website that gives guidance to aspects of architecture that involve Designing for all.
https://www.branz.co.nz/universal-design/universal-design-dimensioned-diagrams/
This link takes you to a website containing existing plans for layouts of small cafes. You can use some of these ideas to help you make decisions about the layout of your design. https://www.roomsketcher.com/floor-plan-gallery/restaurant/coffee-shop-floor-plans/
https://pos.toasttab.com/blog/on-the-line/cafe-floor-plans
This link has some useful minimum room sizes that you could use as research to get you started working out your floor plans https://www.houseplans.co.nz/floor-plans-2/
This concept looks at a triangular layout between the Oven/Stove, the Sink, and the Refrigerator in your kitchen. This concept used to create a kitchen which is both aesthetic and functional by creating good connection between the main task areas in the kitchen.