Selenium trouble finding button - selenium

Question

I have the following code snippet:
enter image description here
I am trying to select the button download in the page:
enter image description here
I am using the following code
from selenium import webdriver
from selenium.webdriver.common.by import By
import datetime
d_ref = datetime.date.today()
driver = webdriver.Chrome('D:\\User\\Download\\chromedriver.exe')
chrome_options = webdriver.ChromeOptions()
prefs = {'download.default_directory' : 'D:\\User\\Download' }
chrome_options.add_experimental_option('prefs', prefs)
driver.get('https://www.anbima.com.br/pt_br/informar/sistema-reune.htm')
# driver.maximize_window()
driver.execute_script("window.scrollTo(0, 320);")
driver.switch_to.frame(0)
# driver.find_element(By.NAME, "Dt_Ref").clear()
# driver.find_element(By.NAME, "Dt_Ref").send_keys(d_ref.strftime('%d%m%Y'))
dropdown = driver.find_element(By.ID, "TpInstFinanceiro")
dropdown.find_element(By.XPATH, "//option[. = 'C F F']").click()
driver.find_element(By.CSS_SELECTOR, "fieldset:nth-child(3) input:nth-child(1)").click()

Answer 1

The CSS-selector fieldset:nth-child(3) is highlighting Financial Instrument and fieldset:nth-child(3) input:nth-child(1) is not highlighting any element in the DOM. Link to refer
Below CSS-selector is highlighting the Download option in the DOM.
fieldset:nth-child(5) input:nth-child(4)
Better to close the Cookie pop-up to interact with other elements. Use Explicit waits.
# Imports
from selenium.webdriver.support.wait import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC
driver.get("https://www.anbima.com.br/pt_br/informar/sistema-reune.htm")
wait = WebDriverWait(driver,20)
# Click on Proceed on the Cookie pop-up
wait.until(EC.element_to_be_clickable((By.XPATH,"//a[#class='LGPD_ANBIMA_global_sites__text__btn']"))).click()
# Switch to Iframe
wait.until(EC.frame_to_be_available_and_switch_to_it((By.XPATH,"//iframe[#class]")))
# Select Download option
wait.until(EC.element_to_be_clickable((By.CSS_SELECTOR,"fieldset:nth-child(5) input:nth-child(4)"))).click()