New to the forum, and also to the dirtbike world, & Have a question about a new device I just bought from my son. It looks like the tire is crooked in comparison to the handlebars. When the handlebars are straight the tire looks a little bit talk to the side. What is the best, and proper way, to fix that? Do I just need to loosen up the bigger nut on the tree? I'm more familiar with 4 wheelers, and just don't want to mess anything up on his new dirt bike.

 

Usually if you hold the tire between your feet/knees and yank the bars the way they need to move it solves the problem . If necessary you loosen the pinch clamps on the fork legs a bit, then repeat the holding with feet/knees and tweak. It won't take much if the clamp bolts are loosened to allow the tubes to slip in them. Just don't loosen to the point where they slide up in the clamps.
Other method often used in the boonies is to pull up to a tree or post and slam the front wheel against the tree to realign it and the forks

Of course, make sure one of the fork tubes isn't bent, handle bar mounts aren't damaged, or something else,