Upon creating your character, you'll awaken in Atlas Park, the starting zone for heroes. Your first objective will be to speak with your Trainer, usually located near your spawn point. The Trainer will provide you with your initial powers and your very first mission. This mission serves as a tutorial, guiding you through basic combat and objective completion.
Look for exclamation marks (!) on your mini-map and above NPCs' heads – these indicate available missions. Question marks (?) indicate completed missions ready for turn-in. Don't be afraid to explore the immediate area, but stick to the mission objectives initially to gain experience and understand the game's flow. You'll quickly level up and unlock more powers, preparing you for greater challenges in Paragon City.