I will need to rent a phone for an up coming trip to Japan. Can I do that in Japan or do I need to arrange it here in the US?

Why will you need to rent a phone?
If you have an unlocked smartphone and add some data to it when you arrive that should suffice for a minimum.

Hotels have wifi and IF you need to make local calls add some money to either viber or skype. I have an android so WhatsApp is what i use to call my friends. We also message on FB.

https://www.japan-guide.com/e/e2223.html

So I use my work phone for most things and the security on it means I can't use it overseas. My husband & I need to be able to text each other away from wifi when we get seperated.

thanks for the Japan guide page, thats what I needed

I'm glad that page helped!

Do make use of japan-guide.com -- it isn't perfect, but it is an incredibly useful site.