Changing the IP of AR300

a dumb question - the ip address for ar300 is 192.168.8.x
my home network is 192.168.0.x
can i change te ar300 to home network 192.168.0.x?

the reason is if i want to login to admin page of ar300 now, i must connect to its wifi first and then login.
if i change it my home network of 192.168.0.x, can i still be connected my home wifi but access admin page of ar300?

How is the AR300 connected to your home network?

ar300 connected to router via ethernet port. (wired)

In the GL interface enable WAN Access, then you can check your main router and see what IP your AR300 was given, and use that IP to access the interface.

In this case, you don’t need to change your ar300’s intranet. As @Johnex says, you only need to enable wan access on gl ui.

i connected router to ar300 by wan.
i connected ar300 to desktop by lan
enabled wan on ar300
gave static ip to ar300 as 206
on my router i can see ar300 under connected devices as 206.
i connected to my home network on laptop and tried to browse ar300 using 192.168.0.206 but couldnt connect.
i connected to ar300 and checked settings - under wan i had an error Upnp service of parent router not enabled.

It doesn’t need Upnp service. Just need open port on router. Could you please have a try to open port on luci? Negative to Network → Firewall → Traffic Rules. You can see Open ports on router.

Filling with the above information and click on Add button, then click on Save & Apply button to apply it.

I had a similar request in the past and that is exactly how I resolved it. You can add even the port to your arm300 assigned IP and it will work without the need for port forwarding for e.g. 192.168.0.x:83

I have another question if someone has an answer. Can I connect with RDP to a machine on a different AP?
My main router is DLink 192.168.0.x
AR300M is 192.168.8.X (connected with WISP to DLink)

I have a desktop that is connected to my main router and assigned IP for example 192.168.0.200
I have a laptop that is connected to my AR300M and assigned IP for example 192.168.8.200

I want to be able to RDP from my desktop machine (on Dlink) to my laptop (on ARM300M). Can I do that? If yes, any hints please? Thank you.

Yeah! You need to add a static route rule on your main router. Most of routers support configure static route on ui.