How do I make it so a certain user's leaderstats in my game stay the same and won't change?

Try:

local players = game:GetService("Players")

players.PlayerAdded:Connect(function(player)
    local lead = Instance.new("Folder")
    lead.Name = "leaderstats"
    lead.Parent = player
    local deaths = Instance.new("IntValue")
    deaths.Name = "Deaths"
    deaths.Parent = lead

    player.CharacterAdded:Connect(function(character)
        local hum = character:FindFirstChild("Humanoid")
        hum.Died:Connect(function()
            deaths.Value = deaths.Value +1
        end)
    end)
	deaths.Changed:Connect(function()
		if player.Name == 'name here' then  -- Name for which player has the stats stay on
			deaths.Value = number which is stuck on
		end
	end)
end)

Paste it