food and drink – Do I need visa for sightseeing in Istanbul, April and May 2021


Not-so-young but still adventurous American woman traveling alone with two layovers in Istanbul airport:

Wednesday April 7, 2021, 4:55 pm to 1:30 am that evening – 8+ hours

Tuesday May 4, 4:55 am to 6:20 pm – 13+ hours

Questions

Do I need a visa to leave airport for sightseeing in city?

What is best way to arrange a guide for evening portion?

What is best way to arrange a guide for daytime portion?

How much time do I need to arrive before flight?

How much can I see in these time frames?

What is best food to experience?