Ancient Romans had very simple food habits. Bread was often the single most eaten item. Some would use honey or cheese to sweeten the bread and eat it along with sausages, eggs, cheese, or shellfish.
A typical Ancient Roman’s food for the day would be 1) Breakfast – eaten very early as soon as the sun rose and this would include fresh fruit and bread. 2) Lunch – was a small meal eaten around noon, and 3) Dinner – was a big meal that would start around 4pm and continue into the night. Food was generally eaten with fingers whilst sitting on the ground or on couches. It was considered distinguished to eat with three fingers, keeping the ring finger and little finger clean while eating. The "commoners" would eat their food with all five fingers.
To survive in Ancient Rome from a food perspective, be prepared to eat a lot of bread and fruit. Timings and quantities also vastly differ compared to the era in which we currently live and you should be able to adapt to these timings. You will need to learn to eat with your fingers and be prepared to sit on the floor or on a couch. Remember to eat with three fingers, keeping the ring finger and little finger clean while eating so as to look polished rather than a commoner.