How to merge 2 seperate LAN

[eikhidero]

Hello,
I have 2 seperate Lan on my network one i use for VPN connection to my head office (192.168.21.1) and the other which i use for internet connection (192.168.1.1)The challenge i face nw is both connection can't run at the same time, now i want to merge both so i can access the VPN connection and the INternet at the same time. what do i need to do??

 

[gtvr]

Not enough info. What is the setup - routers, PCs, internet connection, etc. How are you connecting your VPN?