How to use context provider in webpart ts file

I am trying to use context provider in webpart ts file but i can't able to add context provider in it i don't have route files.First i add context provider in tsx file but the state variable gettting null value the data isn't passed in context.

AppContext.tsx:

import React, { createContext, useContext, useState } from "react";

const ThemeContext = createContext<any | null>(null);

export const useAppContext = () => useContext(ThemeContext);

export const ThemeProvider = ({ children }: any) => {
  const [state, setState] = useState({ theme: "red" });

  return (
    <ThemeContext.Provider
      value={{
        ...state,
        setTheme: (theme: any) => {
          setState({ ...state, theme });
        },
      }}
    >
      {children}
    </ThemeContext.Provider>
  );
};

App.tsx:

<ThemeProvider>
     ....
</ThemeProvider>

some component:

import React, { useState } from "react";
import { useAppContext } from "./AppContext";


function ...() {
  const { theme, setTheme } = useAppContext();

  return (
   ...
  );
}
export default Theme;