Linux is not Windows. Lots of folk move to Linux expecting it to be basically the same thing with a few different badges. A bit like the automotive differences between Toyota and Ford. Linux is really nothing like Windows! Even those distributions that claim to be very like windows are not really. They just look like it. With added graphical user interfaces that make it look a little like windows. It i in these huge differences that folk start to have issues. Linux at it's heart relies on the user to make seriously good decisions about security and user access and is still command line based. Often your decisions must be at odds with those recommended by the distribution to maintain that Windows ease of use. I does not sound to me like you have made use of the instruction on your distributions website provides that tell you how to install and update software. See https://community.linuxmint.com/tutorial/view/1525

Thanks Matt.