I'm trying to make this tutorial: drone
On minute 8:53 in edit mode he select only the top part.
If i make tab then a it will select all the object if i try using B or C in edit mode it still selecting too much not the whole object but also not the top surface.
This is how it looks like in the video:
And this is how it looks like when i select it:
Both the border select B and circle select C will add to the existing selection. I expect you still have the bottom of the tube selected when you are trying to select the top.
Pressing A will first select all vertices, pressing it again will then deselect all. First deselect all and then select the top vertices that you want. You can also click on one of the top vertices, which will deselect any previous selection and then use border or circle select to select the rest.
Another option is to change to face select mode which will allow you to select the top face, which will deselect previous selections.