Here's a suggested itinerary for 5 days in Mexico City:

Day 1: Arrival and Exploration

• Arrive in Mexico City and check into your hotel
• Start your day with a traditional Mexican breakfast at a local cafe
• Visit the historic center of Mexico City, including the Zocalo, the Metropolitan Cathedral, and the National Palace
• Take a stroll through the beautiful Alameda Central Park
• Visit the Palacio de Bellas Artes, a stunning art nouveau building that houses a theater and museum
• End your day with dinner at a local restaurant, trying some of the delicious Mexican cuisine

Day 2: Teotihuacan and Frida Kahlo Museum

• Take a day trip to the ancient city of Teotihuacan, located just outside of Mexico City
• Explore the impressive pyramids of the Sun and Moon, as well as the Temple of the Feathered Serpent
• Return to Mexico City and visit the Frida Kahlo Museum, also known as the Blue House
• Learn about the life and art of the famous Mexican artist, and see some of her most famous works
• Enjoy dinner at a local restaurant, trying some of the delicious Mexican cuisine

Day 3: Chapultepec Park and Anthropology Museum

• Spend the day exploring Chapultepec Park, one of the largest urban parks in the world
• Visit the Chapultepec Castle, a historic castle that now houses the National Museum of History
• Take a stroll through the park and enjoy the beautiful gardens and lakes
• Visit the National Museum of Anthropology, one of the most important museums in Mexico
• Learn about the history and culture of Mexico's indigenous peoples, and see some of the most important artifacts from their civilizations
• End your day with dinner at a local restaurant, trying some of the delicious Mexican cuisine

Day 4: Xochimilco and Coyoacan

• Take a day trip to Xochimilco, a neighborhood in the south of Mexico City known for its canals and colorful boats
• Take a ride on a trajinera, a traditional Mexican boat, and enjoy the beautiful scenery and lively atmosphere
• Visit the nearby neighborhood of Coyoacan, a charming colonial neighborhood with beautiful architecture and a lively arts scene
• Visit the Casa Azul, the former home of Frida Kahlo and now a museum dedicated to her life and art
• End your day with dinner at a local restaurant, trying some of the delicious Mexican cuisine

Day 5: Markets and Street Food

• Spend your last day in Mexico City exploring the city's vibrant markets and trying some of the delicious street food
• Visit the Mercado de la Merced, one of the largest markets in Mexico City, and browse the stalls selling everything from fresh produce to handmade crafts
• Visit the Mercado de San Juan, a gourmet food market with a wide variety of local and international foods
• Take a street food tour and try some of the most delicious and authentic Mexican dishes, such as tacos al pastor, tamales, and churros
• End your day with a farewell dinner at a local restaurant, trying some of the delicious Mexican cuisine

I hope this itinerary gives you a good idea of what to do during your 5 days in Mexico City! Let me know if you have any questions or need any more suggestions.