"Can I add more controls for thirdy parts to the Basic4Android Designer?"
May be thinking of Third Party Controls - or as Android calls them - Views (in B4A). In Delphi, we had access to many different types; DBcontrols, Image buttons, etc. that usually came in the form of library bundles.
Custom libs and classes in B4A add more controls (views) to jazz up your project, but the designer "Add View" list contains most (if not all) stock controls (say "views" - it took me awhile too) and that's it.
New comer's should start with the beginners guide - since Android is different from what you know now ( it is awesome ). Don't worry, you will "get it". Then the fun begins... - for most - in less than a week.
thread will likely be moved to proper section - Questions.