executable_path
executable_path is the parameter through which users can pass the absolute path of the GeckoDriver binary overriding the system path of GeckoDriver binary to be used for Firefox 47.0.1 and greater.
Example
from selenium import webdriver
from selenium.webdriver.firefox.options import Options
options = Options()
options.add_argument("start-maximized")
options.add_argument("--headless")
driver = webdriver.Firefox(options=options, executable_path=r'C:\Utility\BrowserDrivers\geckodriver.exe')
driver.get("http://google.com/")
But in your code trials you have passed the absolute path of the Firefox binary instead of the GeckoDriver binary. If your usecase is to pass the absolute path of the Firefox binary as well you can use the following line of code:
from selenium import webdriver
binary = r'C:\Program Files\Mozilla Firefox\firefox.exe'
options = webdriver.FirefoxOptions()
options.binary = binary
options.add_argument("start-maximized")
options.add_argument("--headless")
browser = webdriver.Firefox(firefox_options=options, executable_path="C:\\Utility\\BrowserDrivers\\geckodriver.exe")
browser.get('http://google.com/')
GeckoDriver in Google-Colaboratory
You need to install the geckodriver, firefox and selenium and add the path to your path variable within your system or copy within the bin directory and you can use the following solution:
# install firefox, geckodriver, and selenium
!apt-get update
!pip install selenium
!apt install firefox-geckodriver
!cp /usr/lib/geckodriver /usr/bin
!cp /usr/lib/firefox /usr/bin
from selenium import webdriver
binary = '/usr/bin/firefox'
options = webdriver.FirefoxOptions()
options.binary = binary
options.add_argument('start-maximized')
options.add_argument('--headless')
browser = webdriver.Firefox(firefox_options=options, executable_path='/usr/bin/geckodriver')
browser.get('http://google.com/')
Update 1
As per the error you mentioned within the comments, as you are using ipython the options should be passed within single quotes as start-maximized and --headless. Additionally, while specifying executable_path there shouldn't be any space character between the raw string literals marker and the string
You can find a relevant discussion in SyntaxError: invalid syntax with executable_path in ipython
Update 2
For GeckoDriver, Selenium and Firefox Browser compatibility chart you can find a relevant discussion in WebDriverException: Message: invalid argument: can't kill an exited process with GeckoDriver, Selenium and Python on RaspberryPi3
