It's pretty similar to a 1 v 1 fight:
At the beginning of each exchange, the group figures out what the characters involved are trying to do during the exchange. Generally, this means each player declares their PC's action and the GM declares the NPCs' actions, but there can be some back and forth when a character's intended actions come as a surprise to someone who's already declared.
Once what everyone's attempting is settled, then dice are rolled (you might need multiple rolls for a single character or no rolls for a character depending on what they are trying to do) and the GM, seeing the results, says what happens. Characters that are affected by hostile actions might take wounds.
Since you're using dramatic weapons and armor:
When people roll, keep in mind the situation they are rolling in. You might give someone a +1 for attacking with a weapon drawn from concealment, or a -1 for a height disadvantage, or a +2 truly exceptional situational modifiers (anything bigger than +2 and you probably shouldn't be rolling-- no roll is needed when two thugs try and shoot Superman with 9mm pistols. They just lose).
Party size is a huge deal in FATE. If you treat someone as a full character, they will have a decent chance of beating PCs because they only need their aspects for this one scene whereas the PCs need to save aspects for later. The PCs have Fate points, but those are even more permanently consumable resources. This is fine for a 1 on 1 or even 1 on 2 fight versus important major characters, but you shouldn't treat average mooks the same way you treat the PCs unless you want a very low-powered game.
There's two ways I handle groups of enemies in FATE 2.0 when the PCs are intended to be worth several of their opponents:
1) group the enemies. FATE 1e has some advice on that, but I didn't find that out until recently so the way I've been doing it is a little bit more simplified. You just treat a group like a single character with some extra hp (like an extra Injury box, Hit box, and Clipped box, for a good size group, but use GM discretion). It has aspects and skills and it tries to do stuff, generally via its members. You can even give it bonuses for using particularly excellent members or specialists at a thing or whatever, and penalties for newbies or specialists at a different thing or whatever (as per the dramatic equipment system-- think of the members as its weapons, basically). This cuts down on the number of wounds the group can inflict to a single character in a round, and allows the PCs to fight a single (albeit usually increased in hp) wall of hp with a reasonable number of boxes instead of dozens or hundreds of boxes if you ran them individually. Like if your party is fighting a band of 20 kobold ambushers, they have literally 140 total hp in the default system. Don't do that to yourself.
2) Give the enemies terrible stats. There's an inclination when GMing FATE 2.0 to give enemies stats that resemble the PCs in magnitude. Don't do that for groups. If the baseline stat for each enemy is around TN-2 (the TN being the amount required for an 'average' PC success roll in your campaign. Not average on the ladder, the average thing your PCs are normally rolling against) the battles will work out better. That makes an average success move the fight moderately in the PCs favor (a 'hit' result) rather than do literally nothing (a 'scratched' result), which I think is a VERY significant improvement. It also means an average defensive roll can take a -2 and still be pretty safe, which is good when the enemies are probably getting at least +1 to their rolls against someone every round.
In short, you can run it the same way as normal, but you need to keep in mind that makes the fights very hard, so you proabably wanna only do that sometimes and run them differently the rest of the time.