Deleting a blog

So I have been on WordPress for a few months now though I am still trying to understand a lot of it. I wanted to know what I should do in regards to deleting a blog?
I created my first blog when I began on wordpress but I stopped using it and created a new one under the same account. This one I use all the time and have made my main wordpress account. Only issues is, when I comment on other peoples blogs, I appear as my old blog which isn’t what i want and so I want to remove the blog all together. I looked up how to delete it and I have to do it through the blogs admin (of course), but I’m scared to remove it just in case it removes my other blog. Both blogs have different URL’s and when I did go to try and delete it, all it asked was if I wanted to remove that particular blog, but I can’t be sure if thats what will happen. Really need some advice in what I can do or how I can stop from commenting on peoples blogs with the wrong account.