There is no available pages or built-in functions to list all the questions with answers. If you want so, you need to develop your own custom page.
Plenty of things to do: first, you need to create a custom page plugin
https://docs.question2answer.org/plugins/modules-page/ . In the main content, you will need to do one or more MySQL queries to pull the data in the qa_posts table. There are several built-in functions that you can adjust. Quite difficult if you look at those the first time. If you are comfortable with MySQL queries, it's much easier to proceed things.
Below is a simple way to get the answers I used, but you can also learn about other Q2A functions to list questions.
$answers = qa_db_read_all_assoc(qa_db_query_sub('SELECT DISTINCT parentid FROM `qa_posts` WHERE type = "A"'));
Next step is to display data.
Pagination is a part of qa_content in your custom page, there is also a built-in function to do so.