Nanite Parameters

Hello everyone,
I have created a metro project ( that does not have billions of poly. At this level the video lags and I’m barely running at 15 fps. I have a decent PC config RTX 3060TI / 32G Men / I7 3.80Ghz. I have much less poly than the UE5 demo and yet I have trouble moving with the camera. It’s like Nanite doesn’t work, but I have my triangle mesh…
Is there a parameter that I forgot? Thank you for your answers. Have nice day!

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