The short answer: You do not need to speak Thai or memorise a rulebook. A few concepts and respectful habits make the first session easier.
Kru and nak muay
Kru is a respectful word used for a teacher or coach. Nak muay means Muay Thai fighter or practitioner. Use the names and forms of address the gym team introduces.
Pads, bag, clinch
Pad work uses a coach or partner holding targets. Bag work lets you repeat strikes on a heavy bag. Clinch is the close-range part of Muay Thai involving control, balance, knees, and positioning.
Respect the room
Listen when the coach demonstrates, avoid stepping on equipment, keep training gear clean, and do not treat another student's pace as a challenge you must answer.
Ask instead of guessing
If you do not understand a drill or custom, ask. Clear communication is more respectful than pretending to understand and creating an unsafe situation.
Use current gym information
Prices, schedules, policies, and coach availability can change. Use the current prices and schedule, then use the training planner for the next step.