Advice about Freelancing

Hi everyone , I want to know if there are any freelancers out there or have knowledge of it ? I want to start freelancing and made an account on fiverr and upwork but I don’t know to start initially. Also, would leaving the job in the long run be fruitful for the sake feelancing as I see a lot of people make a lot more than corporate job. And last but not the least , I see a lot of people struggling to get money out of clients.