Question I am trying to get started to use kunena for a website!

You can find the answers to questions like Local Area Network and Domain Names if you use Google.

No, it's not a simple matter of getting hold of a sub-domain for free, not unless the owner of the domain allows it. That's something you have to negotiate with the owner of the domain. If you own your own domain, you can use any sub-domain name that you like (if you want). For instance, suppose you owned the domain tom.com; you could create a site called kunena.tom.com or another one called myhobbies.tom.com and so on and so forth. People who obtain their own domain names usually acquire them through a domain name registration service provider. The cost varies from provider to provider. Normally, you obtain the right to use the domain name for a limited time after which you need to renew your licence. A typical price for a .com domain name is about $5 a year for two years. Acquiring a domain name does not equate to having a webhosting provider. That's a separate issue.

Suppose you buy your internet hosting plan though sozzled's international webhosting company (sozzleds-iwc.net). And let us say that this fictitious company allows its users who don't own their own domain names to use their domain. They might let you use tom.sozzleds-iwc.net. These kinds of options vary between webhosting companies. Again, a phone call to them can answer this question.

Ok, i live in Michigan in the USA. i play a game called jade dynasty and my alliance is called DarkOath, if i make a local area site, would people from let's say Miami, Flordia be able to view it?

A Local Area Network (or LAN) means the computer or two or more computers that are locally connected via a network bridge. They may be wired together or they may be connected wirelessly. Typically, if you live at home, this means the computers connected within the house. In order to get out of your house to someone else's house you need to use the internet.

Like I said, if you Google the definition, it's explained in much better detail than I am attempting to provide to you.

what is a cheap domain service that you use for your website? that is $5 a year? for 2 years?

also how would i setup a joomla or kunena website with a domain that i buy?

Tom, with the greatest respect, you need to understand a lot more about how the internet works. At this time, the only cost that I strongly urge you to make, is to invest your time in research or, perhaps, the cost of purchasing a good book on the subject. It might be helpful to you to discuss these matters with a school teacher who, I'm sure, can point you in the right direction. Everything that I have attempted to explain to you is much better set-out in the literature that I have referred to.