How can I select a huge amount of values when saving?

Yes, I did use a simulator tutorial script because I'm not good at services.

I'm trying to save a huge chunk of values and I used :GetChildren() and it doesn't work.

I'm trying to find an alternative way to save tons of values without putting tons of functions.

Here is the script:

local DS = game:GetService("DataStoreService"):GetDataStore("StatData")
game.Players.PlayerAdded:Connect(function(plr)
    wait()
    local plrkey = "id_"..plr.userId
    local savevalue = plr.leaderstats.Coins
    local savevalue2 = plr.leaderstats.Gems
    local savevalue3 = plr.leaderstats.Power
    local savevalue4 = plr.Stats.ElementInv:GetChildren()
    local savevalue5 = plr.Stats.PetInv:GetChildren()
    local GetSaved = DS:GetAsync(plrkey)
    if GetSaved then
        for e = 1,#savevalue4 do
            for a = 1,#savevalue5 do
                local save4 = savevalue4[e]
                local save5 = savevalue5[a]
                savevalue.Value = GetSaved[1]
                savevalue2.Value = GetSaved[2]
                savevalue3.Value = GetSaved[3]
                save4.Value = GetSaved[4]
                save5.Value = GetSaved[5]
            end
        end
    else
        for e = 1,#savevalue4 do
            for a = 1,#savevalue5 do
                local save4 = savevalue4[e]
                local save5 = savevalue5[a]
                local NumbersForSaving = {savevalue.Value, savevalue2.Value, savevalue3.Value, save4.Value, save5.Value}
                DS:GetAsync(plrkey, NumbersForSaving)
            end
        end
    end
end)
game.Players.PlayerRemoving:Connect(function(plr)
    local savevalue = plr.leaderstats.Coins
    local savevalue2 = plr.leaderstats.Gems
    local savevalue3 = plr.leaderstats.Power
    local savevalue4 = plr.Stats.ElementInv:GetChildren()
    local savevalue5 = plr.Stats.PetInv:GetChildren()
    for e = 1,#savevalue4 do
        for a = 1,#savevalue5 do
            local save4 = savevalue4[e]
            local save5 = savevalue5[a]
            DS:SetAsync("id_"..plr.userId, {savevalue.Value, savevalue2.Value, savevalue3.Value, save4.Value, save5.Value})
        end
    end
end)