Insert, Recall and Show information from database help

I am developing a plugin for my site, but require some help as I do not know how wordpress does the following actions.

What query should I run if I want to insert into a database?
What query should I run if I want to recall (select) info from a database?

Lastly, how do I show this information in a table, like the content (edit menu) is shown – once I have recalled it?

Thanks