How to fix the position of the code, its not working

Question

How to call the get method after the user has entered any data? I tried many things and I am so upset because this is the main computational function in my program.

I am trying to transmute grades and my main problem here is that I cannot convert the string to float/int so the process cannot be continued in any way.

    def gen_avg():
        # new window again
        genWin = Toplevel(ws)
        # sets the title of the new window
        genWin.title("Class Record Program | General Avg")
        # sets the geometry of toplevel
        genWin.geometry("750x400")
        # change window bg
        genWin.config(bg='#FFF0F5')
        # frm
        frame2 = Frame(
            genWin,
            padx=40,
            pady=50
            )
        frame2.pack(pady=20)
        Label(
            frame2,
            text='My name | Quarterly Grades'
        ).grid(row=0, column=1)

        Label(
            frame2,
            text="ICT Q1 Grade: "
        ).grid(row=1, column=0)
        Label(
            frame2,
            text="ICT Q2 Grade: "
        ).grid(row=2, column=0)
        Label(
            frame2,
            text="ICT Q3 Grade: "
        ).grid(row=3, column=0)
        Label(
            frame2,
            text="ICT Q4 Grade: "
        ).grid(row=4, column=0)
        Q1_tf = Entry(
            frame2,
            font = ('sans-sherif', 15)
        )
        Q2_tf = Entry(
            frame2,
            font = ('sans-sherif', 15)
        )
        Q3_tf = Entry(
            frame2,
            font = ('sans-sherif', 15)
        )
        Q4_tf = Entry(
            frame2,
            font = ('sans-sherif', 15)
        )
        # position the entry boxes
        Q1_tf.grid(row=1, column=1)
        Q2_tf.grid(row=2, column=1)
        Q3_tf.grid(row=3, column=1)
        Q4_tf.grid(row=4, column=1)
        Q1 = Q1_tf.get()
        Q2 = Q2_tf.get()
        Q3 = Q3_tf.get()
        Q4 = Q4_tf.get()

        Button(
            frame2,
            text="Compute General Avg.",
            pady=4,
            padx=30,
            command=(genAvg)
        ).grid(row=5, columnspan=2)

    Button(
        frame1,
        text='Display Transmuted Grade',
        pady=4,
        padx=40,
        command = disp
    ).grid(row=12, columnspan=2)

    Button(
        frame1,
        text='General Avg.',
        pady=4,
        padx=30,
        command=(gen_avg)
    ).grid(row=13, columnspan=3)

    def genAvg():
                        
        gen = int((Q1)+(Q2)+(Q3)+(Q4))
        genz = float(gen/4)


        # dang this took a lot of time -Transmutation table-

        if (genz) < (75):
            pF = 'Student does not have a passing grade this school year.'

# short version of the transmutation table bc its unnecessary

        pf = str(pF)

        time.sleep(2)

        Label(
            frame2,
            text =(pf)
        ).grid(row=5, column=1)
    

Error

File "C:\PYTHON\Python310\rr.py", line 430, in genAvg gen = int((Q1)+(Q2)+(Q3)+(Q4)) NameError: name 'Q1' is not defined