Question #1:  When drivers are configured at environment variables system is not identifying drivers and throwing console errors.  Error details are attached.

browserName="Chrome"

webdriver.driver = None

if(browserName=="Chrome"):
driver = webdriver.Chrome()

elif(browserName=="Firefox"):
driver = webdriver.Firefox(

elif(browserName=="Edge"):
driver = webdriver.Edge()

elif(browserName=="ie"):
driver=webdriver.Ie()

else:
print("No browser is specified")

driver.get("https://www.facebook.com/")
driver.implicitly_wait(5)

fbLogo=driver.find_element_by_xpath("//div[@id='blueBarDOMInspector']/div/div/div/div/h1/a").text
print(fbLogo)
driver.close()