How do I disable clam shell mode and still use 2 monitors?

You don't.

A plain M3 chip only supports two displays, total. To drive a second external display, the M3 MacBook Air must take hardware resources that would normally support the built-in screen and use them to support an external one. This is an improvement over the abilities of the M1 and M2 MacBook Airs, which only supported a single external display – period – regardless of whether their lids were open or closed.

Use dual monitors with your MacBook Air and MacBook Pro with M3 chip - Apple Support

The M4 MacBook Air supports using two external displays with the lid open, and is the first M-series MacBook Air to do so. But that involved the addition of hardware to the plain M4 chip.

You don't.

The M3 based MacBook Air supports the internal display + one external display or 2 external displays when in clamshell mode.