If you can see the clog near the top of the drain:
Here is a step-by-step guide on how to handle this situation. how to unclog a toilet filled with poop
If none of these work after 30 minutes of trying, stop. You need a (also called a closet snake). These are $20-$30 at a hardware store. They are designed to crank through the toilet’s curved trap without scratching it. If you can see the clog near the
Angle the plunger to fill the rubber cup with water as you lower it into the drain. This minimizes trapped air and prevents dirty water from splashing backward. how to unclog a toilet filled with poop