I'm a loose head prop now towards the end of my career [34 today!]. I must have degressed as I started off as a tight head prop!
In all seriousness well done on the selection. And if I can offer a little advice on what to do, then follow every and any advice from your U16 coaches and try out even those seemingly little peices of advice that seem irrelivent. It might not work for you, but on the other hand its might and if not take you into the highr realms of the game than certainly to plkace that you might otherwise have not thought about {it really is the old boys network in action).
The worst players you get at any levela are those that think they are already good. There is always something more to learn!