Calculator won't calculate

Hi,

I just received my first iMac, and I was attempting to use the calculator. It pops up as normal, you can use the keyboard or click on numbers but, the first number you put in is the only number that it allows, and no functions.

I apologize if that doesn't make sense. For those that do understand my issue, how do I fix it? This the newest iMac that just came out.

Thank you for any advice! ---Ane

Here's a brief video of what is happening.

https://youtu.be/a9spg35Cnd4