involve or include

Please tell me the difference between “include” and “involve”. According to my friend, we use “include” when we say something is a part of something. On the other hand, we use “involve” when we refer to something that is a part of an event, activity or situation.

Please guide me.

In everyday use, that is probably a little too prescriptive as ‘include’ and ‘involve’ are often used as synonyms, with no intended difference.

Even the dictionary definitions don’t really do a good job of separating them:
oxfordlearnersdictionaries.c … sh/involve
oxfordlearnersdictionaries.c … sh/include

I would say that ‘include’ is more direct than ‘involve’. For example we would say that the cost of the car service includes value added tax. In a less direct way we would use ‘involve’ like this - The car service involves checking all the important parts of the engine.

Again -

Are you included in the list of participants in this project?

Are you involved in this project?