Give me a list of important things to take on an international trip

Here's a list of most important things you need on an international trip :

1. Passport and visa : All documents required to get into the destination and get back. Make sure all the documents are valid and are not going to expire within 6 months of your trip.
2. Money : Ensure that you have the appropriate amount of money you need. Check if the debit/credit cards are going to work seamlessly in your destination country. In some places, it is helpful to carry local currency while others might prefer transactions through mobile apps (Wepay, GPay, etc).
3. Medications : Ensure that you have enough supply of any prescribed medications. Even the generic medicines might be hard to find in some places.
4. Clothing : Pack the right kind of clothes, layers, and footwear depending on the destination weather and planned activities.
5. Internet and Phone connection : Plan to have international roaming enabled on your devices or buy local prepaid phone plans. When using your existing phone plan, validate that it supports the network in your destination country. In some countries, the free wifi access requires a local phone number.
5. Chargers and adapters : Different countries use different power outlets. Make sure to carry power adapters and chargers for all your devices. While traveling, it is useful to carry a portable charging bank.
6. Itinerary and reservation details : Carry physical and electronic copies of the travel plans and all reservation details. 
7. Apps and guidebooks : Carry language apps and guidebooks to help you with common phrases and in getting around. Also familiarize yourself with the local customs.