Custom Field Widget in Blog Post

Hello!

Im using wordpress to write about my products and I’m thinking of adding a widget on the right that will display custom fields of my post in that widget.

E.g. Im writing on a computer product, on the right i wish to have a box that list down it’s specs, where i can buy it from etc. each post is of different product and different location i can purchase it.

I understand I can add custom fields, but how do I display it in a box on the right like a widget?