Will has several important meanings:

1. The mental power to make yourself do something, especially when it's difficult. When you force yourself to finish homework instead of playing video games, you're using your will. Someone with strong willpower can resist temptations and stick to hard tasks even when they'd rather quit. Athletes training for competitions, students studying for big exams, and people learning difficult new skills all rely on will to keep going when things get tough.
2. What someone wants to happen or intends to do. “Where there's a will, there's a way” means that if you truly want something, you'll find a method to achieve it. When teachers tell students they can work at will during free time, they mean students can choose what to do according to their own wishes.
3. A legal document that explains what should happen to someone's belongings after they die. In a will, people name who should receive their house, money, books, or other possessions. Creating a will helps families avoid confusion and arguments during a sad time.

The word also appears as an auxiliary verb for the future: “I will go” or “She will arrive tomorrow.”