how to set up alexa app on windows 7

Uuh Microsoft does not have Alexa apps for iOS. Apple does. Also Google owns android. They are also not Microsoft.

The Alexa "app" is installed on a smart phone or tablet (e.g., an iPhone or iPad).  Assuming that you have a new Amazon Echo, instructions are here: 

https://www.amazon.com/gp/help/customer/display.html/ref=hp_left_v4_sib?ie=UTF8&nodeId=202189140

If you have a computer with wi-fi capability (most laptops), you can configure Alexa by going to https://alexa.amazon.com/

In either case you'll have to have (or create) an Amazon account.  If you're going to use your own Amazon account, after you have things set up, you probably should go to Settings > Accounts > Voice Purchasing and either disable purchasing or set a "voice code" for authorizing purchases.  Otherwise, your grandkids may put your bank account on a diet.

Actually the website https://alexa.amazon.com/ states the download on that site won't work with Windows 7 and the newest download only works for IOS and Android.  Even though Win 7 is outdated, I prefer to have it on that platform rather than on Windows 10.

Wonder what MS says about that, or if there is a work around.

WOW... How freaking rude of you. 

You need to work on your customer service manners.  Holy ****!!!!

Lol. I agree with the "go !!!! yourself" sentiment. Microsoft "Answers" is usually just apathetically, negligently useless like quora or yahoo answers. This is the first thread I've seen where moderators are outright !!!!s.

Go !!!! yourselves, !!!!s, and Merry !!!!ing Christmas.