Hi.. im new to all this

[micheus]

You can do it by selected faces or the entire object.
If the whole object will be textured I think select its whole face can be better. In the auto UV window you just need to mark the right edges for cut - not easy task for curved surfaces. It's something you have to Lear by yourself.
Watch many videos about this operation can help to understand where a cut can make easy the next step. But, even you not doing a good cut in the auto UV you will be able to make new ones or revoke other in the UV editor window.
Don't wore about make mistakes, you are learning. There is the option to undo, or even save your project incrementally.