Most of the nationalities require tourist visas for Türkiye.

Here are the countries that they can enter to Türkiye with their national ID Cards and without visas : 
https://www.mfa.gov.tr/countries-whose-citizens-are-allowed-to-enter-T%c3%bcrkiye-with-their-national-id_s.en.mfa

For other countries with their passports, they can visit offical e-visa page :
https://www.evisa.gov.tr/en/

The national language in Türkiye is Turkish(Türkçe). However, tourists will rarely find a problem communicating as English, Spanish, Portuguese, Chinese, Arabic, German & French are mostly spoken in hotels, tourist areas and shops.

Here are the basic words for beginners :
https://www.mondly.com/turkish-words

Turkish National Holidays:
During national holidays, banks and governmental offices are closed. Restaurants and shops do not close; in fact, they tend to be more crowded than usual.

The 2024 Calender is here;

Jan 01 : Monday, New Year’s Eve
Mar 30 : Saturday, Eid al-Fitr First Day
Mar 31 : Sunday, Eid al-Fitr Second Day
Apr 01 : Monday, Eid al-Fitr Third Day
Apr 23 : Tuesday, National Independence & Children’s Day
May 01 : Wednesday, Labour Day
May 19 : Sunday, Atatürk Commemoration & Youth Day
Jun 06 : Thursday, Eid al-Adha First Day
Jun 07 : Friday, Eid al-Adha Second Day
Jun 08 : Saturday, Eid al-Adha Third Day
Jun 09 : Sunday, Eid al-Adha Forth Day
Jul 15 : Monday, Democracy and National Unity Day
Agu 30 : Friday, Victory Day
Oct 29 : Tuesday, Republic Day

It’s customary to tip in Türkiye and you may want to think about carrying small bills in your pocket for this purpose. Visitors would normally consider tipping their tour guide, driver, hotel bell staff and waiters in restaurants.

Recommended Tipping Guidelines:

– Tour Guide: $50.00 per day
– Driver: $25.00 per day
– Escorts for transfers $15.00 per transfer
– Drivers for transfers $10.00 per transfer
– Restaurant and Waiters: 10% – 15% Prefer their tip in cash
– Hotel Housekeeping: At your discretion
– Porters: $5.00 per bag

Hotels, restaurants, bars and cafes sometimes add a 10-15% service charge; please check your bill before tipping.