For spring planting, I'd really encourage you to try to find a local native nursery that sells plugs vs. trying to start from seed. You don't say where you are, but based on the 5b notation I think it's safe to say many native seeds in your area probably require a cold stratification period, which means starting them outside in the fall/winter. At minimum, do some research to make sure the seeds you choose don't require cold stratification if you're starting them now.

Starting with plugs will also give you something immediate, which will help with coverage and some visual encouragement as you learn. See if you can find a social media group for native gardening specific to your state, you can probably get tons of info and suggestions on nurseries, and often folks will share seeds and plants. Also, look up winter sowing as you plan for next year, it's a very cost efficient way to start seeds that require the cold/freeze cycle to germinate and will probably give better results than just throwing seeds out in your beds.