Welcome to the community, your willingness to jump right in is awesome! Any and all questions are welcome here.
Some thoughts:
1) This whole thing is a journey, you'll be able to make some quick changes now but the real rewards come from long-term, sometimes boring, sometimes frustrating, work toward a goal.
2) On the topic of your 401(k) - it would be wise to look into the expense ratio for the funds that your 401(k) reside in, as well as the specific allocation of each of the target date funds. You may find that your 401(k) is costing more than you would like. Don't worry too much about short term returns, the ups and downs of the markets year over year are evened out over the long term.
3) Around here, it's standard practice to 'facepunch' folks - that is, to point out some of the more obvious areas of a budget that could use readjustment. For starters, it seems like you spend a lot on utility costs for your home. Between your mortgage and what appear to be utility and other misc home items, it looks like you're spending a bit over half your monthly income on your home alone.
Also, it would be much more helpful to clarify your income. $3900 is your take-home pay, but what's your gross income?