Sharing this details on a tour developed by us, especially for travelers planning to visit India from Germany, France and Russia.
The tour name of Golden Triangle tour package, and here one can explore the sites of New Delhi, Agra and Jaipur in 4-5 days. Plus, if one can lend extra 3-4 days, then we can add Ranthambore National Park, Udaipur and more cities from Rajasthan state.
In Delhi, some of the must see tourist attractions are Chandni Chowk area, which has sites like Red Fort, Jama Masjid, spice market. Then just 4 km from Chandni Chowk, there is the Rajpath, where one can visit India Gate and Rashtrapati Bhawan. And for more details on what to see in Delhi, check out https://santramholidays.in/delhi-sightseeing-package/
In Agra, the must see sites are Taj Mahal, Agra Fort and Fatehpur Sikri, and you will find more details on how to plan a Agra tour from Delhi at https://santramholidays.in/agra-tour-package/
And finally, if you are interested in visiting all three cities of Delhi, Agra and Jaipur (also known as Golden Triangle City) then check https://santramholidays.in/golden-triangle-tour-packages/ as here you will find more than half a dozens or tour packages for Golden Triangle, along with tour of Udaipur, Ranthambore etc.