Proper greetings, salutations, and goodbyes are extremely important when you meet a francophone (a French‐speaking person). In addition, expressing numbers and being able to tell or ask about the time are essential tools in many circumstances. And being able to express the day, the month, the date, the season, or the weather is beneficial in many social conversations, especially when you're making plans.
Cognates are words that are the same or similar in both French and English. If you know your cognates, simply turn on your French accent and voilà — you're speaking French! False friends, on the other hand, are words whose meanings are deceptive, so you don't want to misuse them and make mistakes.