Weeds or a flowers??
The plant in your first photo looks like a native Jack-in-the-pulpit (Arisaema triphyllum). Flowers and fruits would be needed to confirm the ID. Here are photos for comparison. https://www.marylandbiodiversity.com/view/1654
The plants in your second photo are sedges (Carex sp.). Yellow nutsedge is a type we see commonly in wet areas, but there are many other species of Carex, noted here. https://www.marylandbiodiversity.com/viewChecklist.php?genus=Carex
Here is our profile of the common yellow nutsedge and how to manage it, if it is a problem a lawn. https://extension.umd.edu/hgic/topics/yellow-nutsedge