Opencart web development issues

I downloaded an opencart theme, I used it for an ecommerce platform some features are working well meanwhile some are not working well. 1. View cart: The function works but I need to refresh the screen manually before I can see it, I don't want it that way I want to be effective as soon as I click on view cart. 2. Update cart: This function works after I have refresh the view cart manually but I need to refresh the screen manually before I can see it, I don't want it that way I want to be effective as soon as update the cart. 3. Remove cart: The function works but I need to refresh the screen manually before I can see it, I don't want it that way I want to be effective as soon as I remove from cart. 4. If I should click on any tabs, the items I have in the carts should appear, I should not be refreshing the screen manually before I see the effect. 5. Hashing password to the database 6. Anytime a seller or admin upload items, it doesn't shows directly on the screen, it shows under search and tags. Meaning I need to search the items before I can see the item that was uploaded. 7. On the mobile view I can't see the cart logo on the page 8. After making an order some errors do show at the [login to view URL] page For best understanding visit [login to view URL] Try to add to cart, remove, update and click on another pages to see if the items that are in the cart will be hold and tried to make order as a guest. You will understand better.