In detail:

Usually those fields are filled by experienced NCO like Chief O'Brian at Starfleet's base DS9.
But it will not hurt, if a squad leader at a reconnaissance mission knows a little bit more about camouflage, than how to spell it. Authority and respect dwindle the moment it becomes obvious, that the troops outwit their commanding officers. Especially when it comes to vital knowledge or abilities. To gain and to keep their respect, the troops must be lead by example and not by the number of pins at the collar.

The infantry squads conduct the main thrust during landing operations. They also secure sites, buildings or personnel.

Recon Squad covers the field of reconnaissance and espionage. In "peace time" this means to gather and to confirm data and information. In real combat situations Recons had to cut through the enemies lines and act on their own until reinforcement arrives. This includes actions like "take and hold key positions", or "locate and secure specific persons".

Supply Squad supports the other squads logistically. If necessary they restore combat abilities of wounded warriors in the combat zone itself. More than the other squads, Supply depends on the ability to improvise and to adapt to unknown circumstances in order to handle the needs of the troops.

Tech Squad is responsible of maintenance and control of vehicles and equipment. During landing operations the Techs pilot the vehicles, like shuttle crafts, APC or tanks. They also dismantle self-destruct devices at boarded vessels or stations, in the case, Signal had failed to disengage the programs.