a) He decides to plant some sweet potatoes. First, he weeds all the wild plants growing there, then he prepares to make the beds and sows the seeds.
"to weed" means to get the weeds out. (verb)
a "weed" is an undesireable plant in the garden. (noun)
in gardening, one "prepares" the flower bed or plantng bed. (areas that will be planted)
He decides to plant some sweet potatoes. First, he weeds the garden, then he prepares the planting beds, and then sows the seeds.