How to implement custom input fields in the wp admin, the content of which is displayed in the right place in the theme?

Question

WordPress

How can I implement the following:
In the admin panel on a separate page, create fields for entering text, and the contents of these fields will be displayed in a pre-specified place in the topic. For example, a shortcode or just a piece of code that I will insert during layout.
For example, in premium themes, they do this to enter their own copyright text in the footer.
The fields are needed not in the post/page editor, but in a separate section of the admin panel.
Is it possible to do this with some plugin, or is it just the wp api and the path is just code smoking?

Answer 1

Advanced Custom Fields

Answer 2

How are fully customizable themes created?
Is there a plugin for creating custom options of any type with their grouping?
Setting up Redux is very simple

Answer 3

You can also use the Redux-framework plugin - it creates a separate section in the admin panel for creating your own theme options. It is often used for topics on Themeforest.
If you do not understand how to configure it, then ask questions)