That depends entirely on how you want to experience the game.
Even if you choose to use a mod menu, many players find a happy middle ground: using noclip only for practice (while completing levels without it), or using unlimited money just to unlock icons without affecting gameplay difficulty. Geometry Dash Mod Menu NoRoot Unlimited Money - Noclip
In your Android settings (Security/Privacy), allow the installation of apps from unknown sources. That depends entirely on how you want to experience the game
: Grants maximum amounts of in-game currency like Mana Orbs, Diamonds, and Secret Coins. and Secret Coins.