How do you weld a ship with hundreds of parts together with a script so it can move? (WITH CODES)

I am trying to weld a pirate ship together with code so that it can move through the water. Unfortunately I haven't been able to figure out the right coding. I have tried many different codes but they don't seem to work. Such as:

w = Instance.new("Weld") 
w.Part0 = _____
w.C0 = ____.CFrame:inverse() 
w.Part1 = script.Parent 
w.C1 = script.Parent.CFrame:inverse() 
w.Parent = script.Parent

Just doesn't work

Parts = -- Place where all the blocks are 
Engine = -- Main block 
Get = {} 
for _,v in pairs(Parts:GetChildren()) do if v:IsA("BasePart") 
then table.insert(Get,v) 
if v ~= Engine then 
local Weld = Instance.new("Weld") 
Weld.Part0 = Engine 
Weld.Part1 = v 
Weld.C0 = CFrame.new() 
Weld.C1 = v.CFrame:inverse() * Engine.CFrame Weld.Parent = Engine 
end 
end 
end 
wait() 
for _,v in pairs(Get) do v.Anchored = false 
end

For this code it says It says Workspace.Deck.Script:3: attempt to index global 'Parts' (a nil value)

local prev

for _,v in ipairs(script.Parent:GetChildren()) do

if v:IsA("BasePart") then

if prev ~= nil then

local w = Instance.new("Weld")

local a = v.CFrame:inverse()

local b = prev.CFrame:inverse()

w.Part0 = v

w.Part1 = prev

w.C0 = a

w.C1 = b

w.Parent = v

v.Anchored = false

end

prev = v

end

end

For this code, it doesn't come into any errors but does not work correctly

Please help with code and instructions. The boat needs to be all welded together and unanchored.