The beginning of an event or process is the first part of it.

The beginnings of something are the signs or events which form the first part of it.

The beginning of a period of time is the time at which it starts.

The beginning of a piece of written material is the first words or sentences of it.

If you talk about the beginnings of a person, company, or group, you are referring to their backgrounds or origins.

You use beginning to describe someone who is in the early stages of learning to do something.