How to configure time.spleep correctly - python-3.x

Question

I wrote the code, and need to display notifications at a user-specified time, but for some reason notifications are not displayed at the specified time, what's wrong?
I also tried to assign an int value to a variable, but alas, in this case an error was thrown
from tkinter import ttk
from tkinter import scrolledtext
import requests
import time
from tkinter import *
from tkinter import messagebox
def SiteCheck():
Site_Value = GetSiteBox.get("1.0", "end-1c")
Get_Response = requests.get(Site_Value)
if Get_Response.status_code != 200:
messagebox.showerror(title='Error', message=f"The website \"{Site_Value}\" dont work ")
else:
messagebox.showinfo(title="Successfully", message=f"The website \"{Site_Value}\" work")
time.sleep(TimeCh)
root = tk.Tk()
root.title("SITE CHECKER")
root.geometry('500x300')
ttk.Label(root, text="Enter link to verify",
font=("Times New Roman", 15)).grid(column=0, row=0)
GetSiteBox = scrolledtext.ScrolledText(root, wrap=tk.WORD,
width=57, height=11,
font=("Times New Roman", 12))
GetSiteBox.grid(column=0, row=2, pady=10, padx=10)
Check_Button = Button(
root,
command = SiteCheck,
text='Start checking',
)
Check_Button.grid(row=3, column=0)
TimeCheck = Entry(root,width=10)
TimeCheck.grid(column=0, row=1)
TimeCh = TimeCheck.get()
GetSiteBox.focus()
root.mainloop()