What to look for in stocks before buying them?

I am a beginner investor and have invested in about 6 stocks so far, but haven't yielded any results but I assume that's also due to the fact that market is down? 1. How do you start your search for stocks? Do you just look around in screener? Use existing screeners or what? 2. If you start with sectors, what would be a good way to find these sectors? 3. How do you know a stock is overvalued or not? Can someone give an example? 4. I assume we can use technical analysis to find out when to enter and exit a particular stock? 5. Let's say a company's quarterly results are soon to come, is there anyway you can predict if it'll go up or down? Any resources that might help here? 6. How did you start trading and are there any good books/resources? Youtube is a bit bad and shady.