Normally, I would agree with @wchc (and you should post your code here), but I also recommend you go do this tutorial. It’ll take about an hour and give you a good foundation.
I make this recommendation based on the fact that you are clearly new to these forums, and from this statement (emphasis mine):
These two things say to me that you are likely new to Godot. I make this recommendation because for the player you should be using a CharacterBody2D. There are many reasons for this, and the above tutorial will give you a grounding in many things Godot and then you will have working code from which to refer.
I was actually following this tutorial, and it does use Area2D for the player. I’ve already fixed the issue, and I’ll provide more detailed information when I ask questions next time. Thank you for your advice!