Can an air gap desktop computer be made that can withstand attack by high end hackers

My first time here thank you for the opertunity. please I'm up against some very powerful hacking to my laptops I've lost 3 now I don't know how they do it . I, protecting evidence and have if backed up but it's getting very hard to work with it on my laptops. I've removed wi fit cards from my laptops and they still get in and I'm not connected to my Ethernet . I've heard that a desktop can be more secure from intruders I want an air gap deck top I'll build if to scratch with out a wi fix card of coarse but their are other ways into it I believe" can. Someone please help me pick components that would create a machine that will not connect to the Internet and cannot be breached. Or at least more secure than ,yn3 oeprebious laptops now one more thing I'm getting very strong radio frequency readings bouncing off my door and a couple of Windows in my house I'm using a simple tester but the readings go off the chart . This is wisel blower stuff I'm protecting and may be why I'm up against it here any suggestions would be much appreciated