I'd personally recommend using native plant seeds and not "wildflower" seeds. Seed mixes labelled as "wildflowers" are almost always non-native, hardly beneficial, and sometimes even include invasive species. They are not really "wild" to our area but instead a random assortment of non-native plants from other countries. However, if you use native plants, you will create an ecologically beneficial space for wildlife in your area.
Birds will eat seeds off the ground if they can find them, that is true. Wildlife will always consume some. But usually not enough to cause noticeable issues. When I sow seeds I usually scratch up the surface with a metal rake, broadcast the seeds across the surface, and then gently rake them in just a bit. That helps hide them more from wildlife as well as wind. I usually give them a light watering too just to help them connect to the soil better right from the start.