Most optimization advice is guesswork. This suite measures first, tells you what it is about to do, and lets you undo it.
Six tools, built and used in production on a Unity 6 / URP game,
to make it start : (In Unity Editor) under Tools ▸ Foundation Studios ▸ Optimization Suite
What it does NOT do :
This is not a magic "make my game fast" button. It finds and fixes structural waste (such as) : memory, draw calls, missing LODs, wrong flags. It will not optimize your scripts, your physics, your shaders or your collection.