I'm not a tech type person

I haven't touched any files or changed anything. I just downloaded from the site. When I try to update, I also get script errors along with this error. Is there something I can do to fix it? I'm wondering if it has something to do with my computer, since every time I click on anything here I get * page cannot be found* and have to refresh or use the back button to get to a page. Just seems odd since I can't think of anything that has changed to cause all of this
