trilogy client?
 

is there a way to start your own private server with the trilogy client, not public just like LAN?
Keep in mind, I have no programming background lol.

In short - NO.
The last group of programmers who tried to make Trilogy client work has been at it for nearly 10 years. We still waiting for the results ;)

I know people who have their own private trilogy server, they usually dont answer when I ask how they did it :P my guess is because I dont have any idea how to program and they dont want to walk me through it :P

Well in this case - its a private matter then.
Its easier to take Titanium client and run Trilogy content, than figure out Trilogy client hardly anyone interested in anymore.

kk how do I do it where I have a private titanium server (only me and people on my network) can play on and only have classic content?

You set up a server. Run Minilogin, and disable all expansions past Velious in DB setting.
All of this is described in Wiki guides.
Of course the DB for mobs and items won't truly classic, so any new mobs/items/spells added past Velious would have to be removed manualy.

Just use Akkadius' installer. It'll do all of that with a click.