Hello. Please tell me how this problem can be solved.

I have hAP ax2 with the latest firmware. I need to connect to an open free wireless network via WiFi 2.4 (not mikrotik - without login and password) and distribute Internet in my house also via wireless network.
Ideally, it would be possible to have a home network 2.4 and 5 G (I understand that the 2.4 interface will work in station mode and thus will be busy, but perhaps it can be done with a virtual interface). Speed of operation does not matter much.
Also, the free hotspot asks for authorization by clicking a button on the web page that opens. It is not a problem if each user connected to my home network will have to go through this authorization separately. Also, the home network should not be available on the free hotspot's network.

Problems I encountered:
- in hAP ax2 firmware there is no "station-pseudobridge" mode in WiFi (only ap, station and station-bridge)
- since the access point is not a Mikrotik, "station-bridge" mode does not work (it connects and then immediately disconnects)

As far as I understand, I need to use station mode and then somehow make a NAT for that interface. Unfortunately, I have not found any information on how to do this.

Thanks.

Make sure that, from a default cofig, wifi2 is not part of the bridge. And make it part of the WAN interface list. At last, bind the DHCP client to wifi2 and you should be good to go. If you are going to add a virtual interface to make 2.4GHz available as well, make sure to set it to ap and add it to the bridge.

And don't try to accomplish this through Quick set, you can't.

Tip:
Make an export and search within the export for ether1 (default WAN interface). If you set wifi2 in all the places where it says ether1, you are good to go.

Usually wifi1 is 2.4GHz, wifi2 is usually 5GHz
I think it should be something like this:
- remove wifi1 from bridge
- setup wifi1 as station and connect to the public wifi
- add dhcp-client to wifi1
- setup masquerade in your firewall for outgoing interface wifi1
- add virtual wifi interface on wifi1 for AP, add this wifi interface to bridge

Usually wifi1 is 2.4GHz, wifi2 is usually 5GHz

In the old days, ax devices are the other way around

More a question than an answer, but isn't this example (the one called "Wireless Extender – AX series") what is needed for this use case?
https://remotewinbox.com/mesh-mikrotik/
it uses mode=station, so it should (in theory) not need all Mikrotik devices.

Usually wifi1 is 2.4GHz, wifi2 is usually 5GHz
I think it should be something like this:
- remove wifi1 from bridge
- setup wifi1 as station and connect to the public wifi
- add dhcp-client to wifi1
- setup masquerade in your firewall for outgoing interface wifi1
- add virtual wifi interface on wifi1 for AP, add this wifi interface to bridge

It works. Thanks. Off course wifi1 and wifi2 inversely