1) Please edit your homepage and go to pagebuilder section, now edit the popular courses block and choose the course block with the price and save changes, refer:
http://prntscr.com/bwg309
2) The pricing is added from the woocommerce products only, therefore from front end you create a product and add pricing to the product. Now since the product is connected to the course therefore the product pricing is shown in the course.
In other manner you can say that the course has no pricing of its own, the products are always sold and purchased, if the product is purchased then the access to the course is granted by the wplms.
To give pricing from the backend, you first need to create a product and then connect the product to the course and similarly in backend connect the course to the product. Also make sure the product that you are creating is virtual and downloadable.
Let me know if this helps.