I have never labored by having an htaccess file and thus I am unsure basically have anything correct inside it and I am unsure if I am designed to have one.

I have researched some documentation there has not been much help. Could it be necessary to running an apache server to incorporate an htaccess file?

What’s the significance of htaccess

It allows you configure an internet server on the per-directory basis without restarting the server

where's it situated

Within the directory you would like it to affect

and just how will i determine if mine is correct?

It will what you would like it to complete (that could be a variety of a large number of various things) without clogging your gutters log files filled with errors.

Could it be necessary to running an apache server to incorporate an htaccess file?

Some other webservers also support htaccess.

Can you really fix damaged links while using .htaccess file?

Define "Fix". Server configuration certainly can't make erased content come back.

I have used htaccess on apache servers to password-control this content of the website.

There is a tutorial here: http://www.freewebmasterhelp.com/tutorials/htaccess/3

The Apache Tutorial appears obvious enough in my experience...

To repair damaged links, you could utilize mod_rewrite.