It's great to have a mentor in order to save time and learn things quickly in the right direction, if you are in a college then it become easier to find one as some are really awesome developers who can guide you with their experiences, I found my seniors as my mentors because they gave me a proper exposure to the web development roadmap and tools used by professional developers. Hashnode was also introduce to me by one of them. So if you can't find one then the best option is to read blogs of good developers on medium, answers on quora and hashnode, follow them on github and then you will be able to see the whole roadmap.