How would I make my NPC move?

local p = script.Parent
local dis = 30

while true do wait()
    for i,v in pairs(game.Players:GetChildren()) do
        if (p.Torso.Position-v.Character.Torso.Position).magnitude <= dis then
            script.Parent.Humanoid:WalkToPart(v.Character.Torso)
            print("Walking")
        end
    end
end