how to install office home and student 2019 on a new computer

If your copy of Office has never been installed anywhere, following the instructions for a first time installation should work: https://support.microsoft.com/en-us/office/download-and-install-or-reinstall-office-2016-or-office-2013-7c695b06-6d1a-4917-809c-98ce43f86479.

There is a theoretical possibility that the installation won't activate because it is old, but you should be allowed to do a telephone activation instead.

I purchased this with the new computer February 6, 2017

The Computer sat in a box for years as I was comfortable with my old computer

When it crashed this computer was put into work

I paid extra $129.00 for the Home and Student Office

How do I get it installed

Geo

When did you purchase Office Home & Student 2016? Note that the current version would be Office Home & Student 2019.

Normally, recent versions of Office should be installed via an Office account. For more, see https://support.microsoft.com/en-us/office/download-and-install-or-reinstall-office-2016-or-office-2013-7c695b06-6d1a-4917-809c-98ce43f86479.

I paid specifically for the Student Home Office and I have the receipt and the serial number

I bought a computer and have the serial number.  I do not have the key code. How do I install Office Home and Student 2016?

Note that most Office versions included with new computers are trial versions.

Ask the seller what was included with your purchase.