OCR in the background while displaying findings in GUI - pandas

Question

I am trying to run a OCR function in the background while displaying the findings in a GUI.
The OCR is working fine, but I can't seem to get the GUI started.
I think the issues is that there is not function to start the GUI, but I have not would a solution.
import time
import cv2
import mss
import numpy
import pytesseract
import matplotlib.pyplot as plt
import pandas as pd
from PIL import Image
import PySimpleGUI as sg
import os
import threading
from concurrent.futures import ThreadPoolExecutor
from PIL import Image
import pytesseract
pytesseract.pytesseract.tesseract_cmd = 'C:\\Program Files\\Tesseract-OCR\\tesseract.exe'
def ocr_function():
with mss.mss() as mss_instance:
mon = mss_instance.monitors[0]
screenshot = mss_instance.grab(mon) #Read all monitor(s)
with mss.mss() as sct:
while True:
im = numpy.asarray(sct.grab(mon))
plt.imshow(cv2.cvtColor(im, cv2.COLOR_BGR2RGB))
text = pytesseract.image_to_string(im) #image to text
time.sleep(5) #One screenshot per 5 seconds
os.system('cls') #Clear output
print(text) #Print the output text
return text #Return text to function
#plt.show()
Output = ocr_function
t = threading.Thread(target=ocr_function) #Create a thread for the OCR function
t.start() #Start the OCR thread
Output = df.sort_values(by=['Match_Acc.','D-level', 'R-level'], ascending=[False, False, False]) # Sort columes
Output = Output[Output['Match_Acc.'] >= 1]
font = ('Areal', 11)
sg.theme('BrownBlue')
data = Output
headings = ['Result', 'Column1','Column2','Column3','D-level','R-level','n_matches','nan','nonnan','Match_Acc.']
df = pd.DataFrame(data)
headings = df.columns.tolist()
data = df.values.tolist()
layout = [[sg.Table(data, headings=headings, justification='left', key='-TABLE-')],
[sg.Button('Run'), sg.Button('Exit')]]
sg.Window("Overview", layout).read(close=True)