Can I make NPCs on Minecraft: Java Edition?

You haven't stated the version of Minecraft that you are playing, so not sure if this will work on your version, but try Citizens. It's unfortunately not free, but it does exactly what you're looking for—it has the ability to create NPCs with just right click dialogues to performing different commands.

This is a description of features in brief from the website itself:

  Basic NPCs - right click messages, items, looking around, waypoints, and 
  much more.
  Lots of commands to customise your NPCs
  Extensive developer API allowing scriptable NPCs through plugins such as 
  Denizen.
  Vault-compatible

If you're looking for something free, try this other NPC plugin According to its website, it has the following features:

Drag-and-drop installation
No configuration required
Easy-to-use NPC menu
Many NPC Options
NPC Interaction system:
Player Commands
Console Commands
Messages
Delays
Pauses
Conditions
Cooldowns
Choices
Goto’s
bStats 537 Metrics
PlaceholderAPI 863 integration (optional but recommended)

To create NPCs, open your inventory (type E) and add a Spawn Egg to your inventory. Place the Spawn Egg to create an NPC. To program an NPC, right click the NPC to bring up the customize screen. but since there is Np spawn egg, it's tough to say.