how to set up vpn for use with verizon network extender

I am utilizing Hughes Net Gen 4 connected to an Apple Time Capsule for my home internet requirements. I have purchased a Verizon Network Extender to enhance cell phone service in our 3000 sq ft home. The network extender requires an ethernet connection that will allow vpn, how to I configure Time Capsule to accomplish a vpn connection?

Best Regards,

Don