Schema Builder is a tool that lets you visualize and edit your data model. It’s useful for designing and understanding complex data models.
Step 1 : From Setup, search for and click Schema Builder in the Quick Find box.
Step 2 : In the left panel, click Clear All.
Step 3 : Check Account,Contact,Opportunity,Opportunity Product.
You’ll see something like below image,
Schema Builder is great for visualization, but you can also use it to customize your data model. For example, you can manage the permissions for your custom fields directly in Schema Builder. Just right-click the field name and click Manage Field Permissions.
You can also create objects using Schema Builder. If you prefer, you can create objects in this visual interface if you’re designing your system and want to be able to revise all your customizations on the spot. Let’s see how it’s done.
In the same way you can create fields for the object. Go with schema builder for quick process.