Don't worry about it. If some of your fellow students in the syndicate have a few exercises at the Combat Team level as Troop Leaders or Platoon Commanders then pick their brains. Engineer officers tend to be quite good at the Estimate process.
A Combat Team attack can look quite daunting to put together, but the fundamentals are not that complicated. Once you've made contact with the enemy, you have three basic choices: frontal, left flank or right flank. Part of your force shoots up the enemy and keeps their heads down while the rest of your force takes a covered approach, hopefully at 90 degrees to the firebase, to roll up and destroy the enemy platoon. The FOO will be dropping HE and smoke on the enemy from supporting artillery. Recce and maybe anti-armour will be screening the flank of your assault force.
Whatever you do, you should have at least one Tank Troop in the Fire Base, usually the one that made contact. Expect an obstacle that you will need to breach. (It is considered very rude to not breach an obstacle that someone has put a lot of effort into emplacing). At least one tank troop (and maybe two) in the Assault Force with the Engineers will handle the breach with plows (and maybe rollers). The tanks in the Assault Force then blast through/past the enemy positions, destroying any enemy vehicles that were hidden from the Fire Base. The infantry company roll through the lanes in the obstacle and, accompanied by another Tank Troop in intimate support, destroy the enemy. The infantry dismount as appropriate and stab/grenade the enemy. You consolidate to fend off the inevitable counter-attack, handle casualties/prisoners and then proceed with the task at hand.
You will use the Combat Estimate to make your plan. They will teach it to you, but review it in the Combat Team Operations book.
Above all, don't panic.