The characteristics of paralleled mosfets will not be guaranteed to be exactly the same due to manufacturing differences, tolerances etc, so your design needs to allow for this.
Heatsinking
Paralleled mosfets should be placed close together and use the same heatsink so they are thermally matched.
Current Sharing Resistor
You typically need to use a source current sharing resistor when paralleling mosfets.
PCB traces
For the current carrying traces you should typically star them and try and match the length of tracks to each mosfet from the star source point.
Gate Drive
There is some debate about whether these should be separately driven with their own feedback loop but often its fine to common the gates.
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