HELP OpenWrt + openVPN IP tunelinf, routing, bypass

I installed openWrt on raspberry PI and openVPN everything works ok. I just want to separate the IP on which my PC is from not going to the VPN or that I can occasionally turn it off (while downloading games from steam or while playing to keep my latency lower). I tried everything on Google, but I didn't succeed. can anyone help me. Thank you

EDIT: I use this guide for openVPN

thanks man
I've seen it before but I don't understand it very well. I need newbie instructions if possible