So im new to Banana Pi and I have a few questions

(I have a BPI M2U) First, Why is it that when i boot off the sd card it never asks where to install the system. Second, Why does it not detect my Kingston SSD. Third, Why is the Android image not bootable. Fourth, Why is it that whenever I boot Ubuntu Mate it never actually starts and just keeps restarting. Fifth, What is the U-BOOT Button for? Also is there any ´Windows´ that would work on it?