Custom Template Setup to include custom fields

[Kegan Ball]

I've been searching through the forum here trying to learn how to
create a custom template that has displays all posts from a chosen
category with a custom field.

I've already created the template by just changing the file name to
cat-xxx.php. This changes the displays the posts in that category.

What I want to do is to display the following:
Post Title
Post Content (full content without the option to click on the post
title to expand).
Custom Field
Tags

How do I set this up?

Thank you