flounder
To struggle and move clumsily while trying to do something.
To flounder means to struggle clumsily or helplessly, like a fish out of water flapping around on a dock. When you flounder, you're trying hard but making little progress, often looking awkward in the process.
You might flounder through a piano recital when you haven't practiced enough, stumbling over notes and losing your place. A student might flounder when called on to explain a math problem they don't understand, searching for words that won't come. A person learning to ice skate often flounders at first, arms windmilling as they try to stay upright.
The word captures that feeling of being in over your head. When a conversation turns to a topic you know nothing about, you might flounder as you try to keep up. A swimmer caught in rough waves might flounder, working hard but barely staying afloat.
Interestingly, a flounder is also a type of flatfish that lives on the ocean floor.
Floundering isn't the same as failing. People who flounder are still trying, still fighting. With practice, patience, and sometimes help from others, people stop floundering and find their footing.