How to restore deleted purchases?

So I finally updated my ios and I'm brand new to the new Music app. At first, I didnt understand a thing. I thought Apple downloaded all my songs to my phone so I wanted to delete them off my phone. What I didn't realize about the new update was that you can stream all your purchased songs without having to download the song to your phone. I really didn't understand at first so I started deleting some of the songs I didn't want to keep on my phone (E.g my mom's songs). Then finally I googled something and found out about it. I'm very confused right now and I'm worried that I have deleted those songs forever. i looked everywhere on the itunes app if they were able to be restored in any way. So far I have nothing and the only clue I have of what I can do to get it back is when you click the delete button on a song, it says "You can restore your deleted purchases later from your account summary on your computer"

i am on my laptop now and I still can't find them and I have no clue where to find my account summary and how to restore the songs back

please help!!

iPhone 6, iOS 9.1