First; you may want to start using the search feature, or even just browse the last 3 days worth of threads. There has been a lot of threads on this. I assume that anything you found wasn't helpful, so you will have to describe what you have done so far.
I would start with this:
https://decibel.ni.com/content/docs/DOC-20147
1: Use the USB key provided to install the base packages. (It will appear as a 4GB flash drive, AND a slightly smaller DVD drive. The setup files are in the DVD portion.)
2: Install all of the updates required (All from NI.com)
3: I believe there is a cRIO upgrade that is required.
4: Come back and ask again when you get stuck.
Good luck.