Configration of freepbx

I have freepbx installed on my server here at the building I have a public IP address that allows me to access the freepbx GUI from outside the network am using (Ubiquiti network equipment ) I have GSM Gateway (Dinster2000) linked to the network also can access it from outside the network I have PSTN Gateway (Grandstream GXW410X) linked to the network also can access it from outside the network I have PCI analog telephony (Sangoma) the PCI chip is placed in the PC server of freepbx I have IP Phones (Fanvil 600 + Cisco Cp8865) linked to the same network I want to configure all of these devices and make it work like the attached flow also I want to be able to link to the freepbx using softphone outside the network (note some of required tasks are already works but I need you to make sure that all of this are working fine together + Please I need someone who have experince with freepbx and the gateways I do not wanna wast my time)