In general, there isn't a strict limit to the number of NICs that can be associated with a subnet, but there are practical considerations that come into play.
A subnet with a larger IP address range (i.e., a smaller subnet mask) can accommodate more devices and NICs. Conversely, a subnet with a smaller IP address range will have fewer available IP addresses.
Beside this Network Topology,DHCP Configuration,Network Load etc are also the deciding factors.
So, the number of NICs associated with a subnet is determined by a combination of technical factors and network design decisions.