The core rules mention a number of actions that are possible in exploration mode when a PC is engaged with a scene. Most of these actions are resolvable in a single roll (Aid Others, Consult the Lore, etc), others require you to commit to a series of rolls and refer to random tables (Dungeon Crawl). Either the GM or the PCs can initiate any exploration mode action.
Keep in mind that the actions listed in the core rules are not the only actions a PC can take, but they're the actions that OSR+ supports with specialized mechanics for the game mode. In this section we'll go over each action unexplored by the core rules and how you might resolve it in context.
Sometimes we want to simulate the traversal of a complex space over abstract time. If your adventure isn't actually a dungeon crawl (where you've mapped out various rooms as scenes and are using a battle map with a fog of war to illustrate progress through it), you can still use a dungeon crawl action to resolve a series of scenes as if the PCs had embarked on such an adventure.
This action models PCs' attempts to affect the behavior of NPCs. There are a number of ways you can handle a PC influencing an NPC's behavior, such as contested attribute checks (if the PC is trying to intimidate the NPC, for example) or via mechanics prescribed by the abilities or kits and spells, etc. Finally, when a player wants to influence an NPC over time, you can resort to social combat. The influence others action encompasses all these approaches to resolution.
Investigate the Scene
The investigate the scene action is the one your players will most frequently use when in exploration mode. There is no specific mechanic tied to investigating the scene: the way in which your players choose to explore it determines the mechanics you'll select to resolve their action.