Hey Welcome to the forum!
All peplink devices can make use of a free FusionHub Solo license. Fusionhub is a custom virtual machine that acts as a PepVPN endpoint. Depending on which NAS you have, you can either run it as a VM on your home NAS - so you won’t need OpenVPN at all, or you could run it in the cloud ($5/month on Vultr.com) and get your home router to create a IPSEC / Openvpn connection to the Fusionhub too.
I made a video here about getting a BR1 and Fusionhub working together.
