how to display all content for the people table
There is no table {people} in the database.  However, the way I understand this question, you want to display everything that is recorded about all user entities (i.e. you want the list of user entities that is shown under People in the admin interface expanded to include all the fields attached to such entities).

In that case, you can install the Views project and enable the Views and Views UI modules (both part of the Views project). The recipe below assumes you're using Views 3 on Drupal 7. Older versions are different.

Navigate to Home » Administration » Structure » Views and click Add a new view. Give the view the name "Users", and select "Users" from the Show pull down menu.  Click Save &amp; Exit.  This will give you a page view showing all users, but no fields.

Now, return to Home » Administration » Structure » Views, locate the view named "Users", and click Edit.

Next, locate the "Fields" widget, and click Add.  Filter on "User".  This will show all fields defined for the user entity (except pass), with a checkbox for each.  Check all boxes and click Apply (all displays).  Now you've get to configure how to show each of the fields.  You can of course do a lot of fine tuning here, but I find it better to do that later, after the view is fully populated with fields. So just click Apply (all displays) to each of these.  AFAIK, this gives you access to all the fields in the user entity except pass (which holds the user's hashed password, and is excluded for security purposes).

After you've added all, there will be a preview at the bottom of the page.  At this stage, the listing will not be pretty, but you can fine-tune how this appears later, by editing the format of the view.

When done editing, remember to click Save (near top of screen) to save the view.

If your objective is to export this data, there are deveral modules let you export lists produced by Views. One of these is Views Data Export.