Europe is deindustrializing because they're heavily reliant on expensive energy imports. Before they could buy cheap Russian oil. They also decided to double down on being US vassals despite the US clearly disrespecting them. They either have to import fuel from elsewhere, import way more Chinese renewables, or both, and then their economy can start recovering.

By far most immigrants within Europe are from Europe itself. Those who migrated from elsewhere are providing cheaper labor and doing the jobs white people don't wanna do if at all possible (such as cleaning, delivering food, driving you around, factory jobs, etc). Kicking them out will only accelerate Europe's economies imploding, as the main issue remains one of energy demand and deindustrialization (because energy isn't cheap enough). If you want to look at a European country ran similarly to what you like, look into the way Hungary treats Roma people. It didn't help any Hungarian workers.

If you all need to do a second holocaust to realize that wasn't the problem I'm done with you.