Q.Composting in garden
Is it better to leaves weeds in empty garden space as a cover or to remove and let soil uncovered?

I recommend removing the weeds as much as possible, and covering the area with a black plastic material to kill off any seeds over the winter. Another way to help would be to plant things like clover, peas, beans, or any other legumes, as they add nitrogen to the soil. Here is an article that will help:https://www.gardeningknowhow.com/garden-how-to/projects/how-to-solarize-garden-beds-to-eliminate-garden-pests-in-the-soil.htm