[VB.Net] Read From File/arrays [Help]

Ok so I am trying to write a new program and I am having trouble with arrays and reading from files.

Can someone show me an example code that will load a txt file into an array and then allow me to pick what lines of the text file I want to do stuff with?

Even if you don't use an array is there a way that I can do it?
Any advice?

I have been stuck on this for a while now, any help would be appreciated.