Have you tried typing what is Bitcoin in a search engine online? The answer will be digital currency to be precise but while going deep you will find more use case, e.g.

1. Decentralisation
2. Store of value.
3. No extra printing like money (Limited in supply)

Now it's left for you to pick a side as to what you really need Bitcoin for, use it to your liking, many have comfort in using Bitcoin to make payments online like using credit cards and I do that too but store of value is more interesting to me than anything else.