ACP planner and ACP scheduler are not the same. The following explanations are very high level and very brief.

ACP planner is a standalone support tool for ACP. It is used to build a plan (a script) that ACP executes. Among other options you can select a target, the number of exposures through specific filters, exposure durations, etc. When saving the plan you have the option to upload it to a location that ACP has access to. You then use the ACP console or the ACP browser interface to select the plan you want and then have ACP execute the plan. It is up to you to run the plan when you want it to run.

ACP scheduler handles the when. It takes the entire set of tasks you define using the scheduler bowser interface and decides which one is the best one to run right now based on a set of constraints you placed in the task. You tell it what and it decides when.

Again, these explanations are very simplistic and no where near comprehensive. I highly recommend you get ACP running reliably before adding on the additional capabilities of the scheduler. The best place to start is by watching the videos and diving into the help documentation.