Support and Resitance

Hi guys, how do you go back and identify support and resistance levels, can the previous day’s low and high be constituted as a support and resistance? I get the fib levels but trying to idenify other support and resistance areas is what I’m finding a bit tricky. Also what would be a safe reward to risk ratio, I trade looking at hourly and 15 min charts and use 1:1 rr, is that safe? And finally what would be a safe level of leverage? I know there’s a few questions in there but would really like your support.