There's a few main ways to play Land Druid.
1) You can play as a mage. Using things like Moonbeam, Call Lightning, Wall of Fire, Lightning Bolt, Ice Storm, Cone of Cold and Sunbeam to nuke down enemies.
2) You can play as a support caster. Using things like Hold Person, Darkness, Spike Growth and Sleet Storm to help contol the battlefield. While supporting allies with spells like Healing Word and Haste. You can also summon a bunch of things with the Summon Elementals and Woodland Being.
3) You can play as a hybrid. Where you throw down a concentration spell like Darkness, Sleet Storm, Wall of Fire or Insect Plague and then transform into an Owlbear/Dilophosaurus and go smack things.
Which is probably why it can feel like you're playing the subclass "Wrong", it generally has so much flexibility that you can often find yourself underutilizing some aspect of the class because it does many other things so well. In general, it's hard to go too wrong with Land Druid.
