How to correctly register routing for access to the device with 2 serially connected routers?

Question

network hardware

There are 2 routers, the first one includes fiber (the router holds the 192.168.1.x subnet), then the second router is connected via the lan-wan twisted pair (holds the 192.168.2.x subnet, has WAN IP 192.168.1.10), the second router is connected device.
All ports from the first are redirected to the second, the second is configured to redirect one port 200 to the device (192.168.2.200:200).
When connecting to the second router, 192.168.2.200:200 answers correctly.
When connecting to the first router 192.168.1.10:200 --> 192.168.2.200:200 responds correctly.
When trying to connect externally with INETADDR:200, the device does not respond.
When trying to connect externally INETADDR:8080 (to the web admin panel of the second router), the second router responds correctly, i.e. access through the first router to the second is correct.
But with the initial connection of 2 routers to one subnet (lan--lan) INETADDR:200 (without changes in the first router) answers correctly, i.e. the first router forwards ports correctly.
What is missing to access the end device via INETADDR:200?
There is probably a missing route, but I can't figure out which one.
UPDATED
I noticed that on INETADDR:PORT if there are 2 different answers,
a) If the device behind the port does not exist, then
This site can't be reached
46.44.13.208 refused to connect.
ERR_CONNECTION_REFUSED
b) If I try to reach the camera, which is, but which is not available via the Internet, then
This site can't be reached
46.44.13.208:201 is unreachable.
ERR_ADDRESS_UNREACHABLE

Answer 1

I suggest you disable the firewall and NAT on the 2nd router. Because why is he there?
Also, on the 1st router, register the route to the subnet of the second router.
Device connected to router #2 must have default gateway - router #2 address, and for router #2 Gateway - router #1.
Ideally, you do not need a router number 2 at all, there should be a switch there.