I have archer c6-v2(us) with openWRT 23.05.5 how can i remotely access router settings from anywhere?
Using a VPN to connect to your router,
Consider using WireGuard
See the wiki:
For the road wariror server setup: https://openwrt.org/docs/guide-user/services/vpn/wireguard/road-warrior
Or
See my notes about setting up WireGuard:
You need the WireGuard Server Setup guide
Direct download WireGuard Server Setup guide
You can SSH to it from anywhere around the world, as long as the SSH port is open and the router's IP is reachable. More info about this topic here: https://openwrt.org/docs/guide-user/luci/luci.secure#allow_access_from_internet
Is this safe to do so?
Yes, WireGuard is considered one of the best VPNs to use for remote access to your router/network. It is not 'chatty' so it doesn't show up on port-scan probes, and it only replies when there are valid cryptographic keys used.
I would not recommend exposing other ports, including ssh, if you can avoid it.
@psherman already answered.
I would prefer WireGuard over SSH with regards to safety