Hi again @anas,
some additional hints regarding your geometry: Since there are more than 21 million illegal faces in the model it makes it pretty hard to get a proper mesh. The detailing is a bit too much and might not even be necessary. What I would suggest is to defeature/clean up your geometry meaning that you get rid of unnecessary details if that is possible.
If you still intend to perform a mesh operation you should consider using the parametric mesh option to define the refinements manually. Imho, it is better to defeature all the unnecessary details as this saves you time in the long run.
Please also consider reading through this documentation page: CAD Preperation
Let me know if you have any further questions!