Update Google Map from TextArea of form

I am still getting into Javascript but am attempting to integrate a Google Map with a form I have built on a website. Basically it allows the user to set 2 different addresses (from and to) for a trip. I have 2 Google Maps embedded on the page in 2 divs (id’s of “from-map-canvas” and “to-map-canvas”). What I would like to add is for the maps to update as the user inputs an address into the from-address and to-address textarea fields respectively. Ultimately I would like to calculate out the trip distance between these 2 addresses, so if you have an idea on that as well it would be greatly appreciated.

My limited Javascript abilities I’m sure are my hold-up, but I’ve learnt that I learn best by doing projects such as this so thought I would reach out and see if someone either has an answer, or even a suggestion of a tutorial or website to go check out.