I asked the same question years ago when I first played NWN. No, you can't control a party in NWN. You can have a henchman or two, depending on the module, or you can play on a Persistant World, like a mini-MMO, in which other players can fill out the party.
Part of the fun of NWN is the many possible combinations of classes to make a build. Because they are both based on the AD&D 3.0 rules, multiclassing in NWN is similar to Icewind Dale II, where multiclassing doesn't weaken the character like it did in Baldur's gate, which used the AD&D 2.0 rules.
I got used to controlling just one character, and I have had a blast playing NWN for all these years, and so will you.
If you have questions about making a good build, you can ask them here, or in the NWN Epic Character Builders Guild forums.