Update openwrt instructions (ag-60177)

docs/adguard-vpn-for-linux/setting-up-on-a-router/openwrt.md

@@ -97,15 +97,37 @@ Most Linux and macOS systems come with an SSH client pre-installed. For Windows,
 
 1. Click *Open*.
 
-1. When the Terminal window opens, log in. The default username is `root` and the default password is `keenetic`.
+1. When the Terminal window opens, log in. The default username is `root` and the default password is typically empty (just press Enter), but you should have set a password during the initial setup.
 
 <!-- comment -->
 
 ## 4. Basic SSH commands
 
 Once logged in, you can use various commands to interact with your router’s Linux-based operating system.
 
-Update package lists (OpenWrt):
+:::note
+
+OpenWrt 25.12 and later use the `apk` package manager, while OpenWrt 24.10 and earlier use `opkg`. To check your OpenWrt version, run `cat /etc/openwrt_release`.
+
+:::
+
+### OpenWrt 25.12 and later
+
+Update package lists:
+
+```text
+apk update
+```
+
+Install required packages:
+
+```text
+apk add curl kmod-tun ca-certificates
+```
+
+### OpenWrt 24.10 and earlier
+
+Update package lists:
 
 ```text
 opkg update
@@ -188,7 +210,7 @@ You can do it in the web interface or in the command line. Steps below describe
 1. Add a new unmanaged interface via SSH
 
     ```shell
-    ssh admin@router_ip
+    ssh root@router_ip
     uci set network.tun0='interface'
     uci set network.tun0.proto='none'
     uci set network.tun0.device='tun0'