Once a project has been selected (depending on who holds the purse strings), management will usually select some sort of broad resource plan for the whole project, deciding how many programmers/designers/artists/etc will work on the project, and at which stages in the project lifetime.
The project is often divided up into milestones, which act as checkpoints to verify that the project is being delivered as expected and on time. Less formal projects might have a handful of milestones, whereas big publisher-funded projects often have a formal milestone delivery process where the build is explicitly handed over every so often (monthly, or six-weekly, or quarterly, etc) to be assessed.
Each milestone typically has a bunch of intended 'deliverables' - they are ideally working features, but can also be assets that may or may not yet be integrated into a feature. And there can be different expectations for the state of a deliverable (e.g. "prototype", "working", "finished", etc). The actual state of those deliverables, relative to what was promised, dictates whether the milestone is 'passed' or 'failed'. In the latter case the team is usually expected to fix up those failed deliverables before the next milestone is handed over. If you keep failing milestones, the publisher may terminate the project, as they lose confidence in your ability to complete it.
Scheduling within a milestone is usually done via some sort of agile planning process. With a given set of deliverables in mind, the heads of each department and the project management team ("producers") come up with a list of prioritised tasks and decide who to allocate them to. Those people receive the task descriptions and implement them.
The day-to-day work of each person depends entirely on their job and their task. There may be a 'daily standup' meeting or Scrum where people briefly discuss what they're working on and ask for help if they're stuck. Beyond that, they communicate via conversation/meetings/email/Slack to resolve ambiguities and discuss details. The rest of the time, they're probably at their computer, executing their current task by creating code, art, whatever.