How to use Fedora 37 machine to bridge two wifi cards

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1

I have 2 USB wifi cards on my fedora machine.
I want to achieve:
wifi card 1 connects to the router and has internet.
use wifi card 2 as a hotspot to create a wifi network ( that is different to the wifi that wifi card 1 connects to) .
fedora machine shares the internet connection from card 1 to devices connected to wifi card 2.
devices connected to the wifi that is created by card 2 can connect to the internet.
what I tried: connect wifi card 1 to the internet, turn on hotspot in the network settings, and turn on ip forwarding by editing /etc/sysctl.conf
the results are:
fedora machine can access the internet,
devices are able to connect to the wifi that is created by card 2, but are not able to access the internet.

2

Assuming the default Fedora setup with NetworkManager and firewalld.
For the downstream connection, change IPv4/IPv6 method to sharing and enable NAT66 if necessary:

# List connections
nmcli connection show

# Downstream IPv4 sharing
nmcli connection modify DOWNSTREAM_CONNECTION \
    ipv4.method shared \
    ipv4.addresses 192.168.11.1/24

# Downstream IPv6 sharing
nmcli connection modify DOWNSTREAM_CONNECTION \
    ipv6.method shared \
    ipv6.addresses fd00:11::1/64

# NAT66
sudo firewall-cmd --permanent --add-rich-rule="rule family=ipv6 masquerade"
sudo firewall-cmd --reload
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