[ubuntu_studio] Lenovo IdeaPad 500 15lsk - install ATI Radeon R7 360

Hi guys,
first of all- I am new in Linux. I needed OS for work with videos and photos, so I choosed Ubuntu Studio. I was trying Windows 8.1, but it is so slow in converting videos (I thing that hardware is good enought), that I would like to try Linux.
Installing was easy, but setting things in this OS is pretty hard form me.
First of all, I want to install driver for ATI Radeon R7 360, cause I will need to use these card for better performance.
I tryed install ATI_crimsom_installator_driver-15.302. I generaded driver package, install it and reboot. But system don`t boot any more.
Just black screen shows and writes- /dev/sda2: clean, 325936/60506112 files, 6316981/241998336 blocks.
What I did wrong? Should I use other way to install drivers?
Another question is- laptop has 2 graphic cards- Intel HD graphics 520 and ATI radeon R7 360. Do you thing, that Linux will able to switch between this 2 cards?
Or, how I can switch it manualy, to use ATI?
Thank you for answer.