How to remove imported geometry with references

Hello and thank you very much for your attention!

Basically I have imported a geometry into a part to replicate it and be able to modify it. Now I want to remove the imported parts but of course all the planes I used before lose the references, etc.

Is there any way to isolate them so they just stay in place fixed instead of depending on a reference?

When I delete it it gives a lot of errors:

SolidworksParts And Features