To learn web scarping, start with learning python, and later get familiar with using beautiful soup and urllib libraries. Also, learn the basics of HTML and HTML tags. Learning regular expressions saves time and also will be helpful for web scraping. Get enroll in a good online course to learn all these topics and start web scraping on your own. If you are looking to learn web scraping using python, then check out this Python Certification program by Intellipaat:
You can check out this video on Web scraping using Python to get a quick start with web scraping: