OK, it looks like you have some good choices available. Unfortunately, the target date funds are bit on the expensive side, but you have good index fund options that can cover your bases.
Equity Index Fund should be your largest component no matter what you do with the rest.
You'll want to decide if you want to go for a total market approach, which would invite you to also invest in the SM Midcap Core Index fund. The rough split usually present is 3:1 Large:Mid/Small. So of your 100%, that could be 75/25.
You'll also want to decide if you want to hold international or bonds, and you can use the International Index and Bond Index funds. A target date fund might hold 30% international and, for one your age, 10% bonds. You can decide if you like those percentages or would like to go higher or lower. If you use these funds, obviously scale back your domestic but keep the 3:1 ratio on them for the large and mid-cap split.
See this recent post of mine to see how splits might look under various strategies, replacing the fund names you see mentioned with your own.
As for the Roth, Vanguard has inexpensive target date funds that allow you to truly set it and forget it, so if that's appealing to you, then investigate that option. If you want to be more aggressive than that, you can manage your own allocations to reduce bonds and do whatever with international. I'd say with the first $5500, either do the target date or go into VTSMX (total stock markey, a domestic equity fund), and then reevaluate your allocation next year when you make more contributions, and I'd generally recommend keeping the same general strategy for simplicity if you invest additional funds outside of retirement accounts.
This is all excellent advice. Really appreciate the time and effort to help me out.
Just thought of 1 more question. In regards to the 401k maximum contribution of 18.5k. Is that maximum based on only what I contribute or does that include the 5% that my employer matches? Like can I do 20% and hit 18.5k and then my employer still contribute 5% on top of that? I'm guessing no but figure I'd ask.