How do i manage to get my allocated addresses from someone else VPN ? what about transferring a whole network block via a VPN server ? specially to a home which uses a dynamic IP ?

That is why the proposal is not so simply use a VPN, but to use a VPN and run BGP on top of that. The transfer of your network block to the VPN is handled by BGP. The internet address of the home VPN does not matter, you connect to a VPN server and present some ID (e.g. callsign and password) and the VPN server knows who you are.

Those topics precisely are the improvements in the proposed system, over the existing IPIP system.

Rob