Android Build a Simple Android App Creating the Screen Layout Setting Padding

Android sudio 2.3.3 uses ConstraintLayout instead of RelativLayout

Android sudio 2.3.3 uses ConstraintLayout instead of RelativLayout and that makes the xml really different, for start that is no such thing layout_centerVertical, layout_align..., and so on in the ConstraintLayout and because of the when i position something on the design view by dragging it, it code the text with the methond layout_editor_absoluteX/Y. and also gives me a warning of "this view is not constrained, it only has designtime position, so it will jump to (0,0) unless you add constraints". and i have no knowledge about constraints. i did found the button "infer constraints" which fix this warning automatically but it adds a lot of code to that and that code i don't even slightly understand. and in you videos you don't seems to teach it. I would like to know how can i learn something when their are so many things different in the videos then in my computer.