Can a board have two power supply circuits?
No, each power rail must be supplied by only one power supply. (Having multiple power rail voltages is common, but each power rail is supplied by a single power supply.)

The problem with attempting to drive a load with two different power supplies, is that the supply voltages will not match exactly.

Consider two power supplies that are both "nominal" 3.3V output. Suppose one supply has its setpoint regulating at 3.301V and the other has its setpoint regulating at 3.299V. If these two outputs are wired together, then the (slightly) higher voltage supply ends up doing all of the work.

Even if both supplies happened to be at exactly 3.300V under room temperautre condition, the setpoint will change with temperature variation. And once one supply begins carrying more of the load, that supply will get hotter, causing more mismatch.

The right way to approach system power supply design, is to determine the total load current needed and then design or purchase a power supply module capable of delivering the required load current.