Can't get past disk utility.

I was getting the media kit error because I didn't have enough room on my partition or something like that. So after like 2 hours of searching and trying to understand I finally got the error to disappear, but now I can only use 134 MB of a 240 GB SSD. I am very new to this and a lot of it really confuses me so if you could try to explain in detail what I could do that would be much appreciated.

Thanks.

note: I have access to windows.