I'm a noob and overwhelm.

New member here. I need some help regarding support/resistant and trendline.
If you know resistant/support level then how do you know the market will go one way or the other? what about trendline? what about price action?

Is price action the most important indicator in trading?

There is a library's worth of info on these subjects. Opinions will vary from one person to another.
Most might agree that if the price is above a trend line then that line is support...if it's below then it is resistance.
Your questions are very vague...you might do some google searches or watch some you tube videos or even search this forum and see if you can be more specific. That will save a lot of time.

What i'm asking is how do you decide that stock abc is bullish, bearish or neutral after drawing the r/s line.

I'm going to guess if it's going up then Bull, if it's going down then Bear...if it's going sideways then neutral.
But I tend to either trade short term trends or fade extreme moves. But I prefer the Random Walk Theory for long term expectations. Meaning long term movement tends to be generally random minus the positive drift of interest rates.

As for current overall market assumption...I feel that most of the risk is to the downside as the market is near all time highs, in my opinion, mostly due to artificially low interest rates and other Gov stimuli which could all come unraveled at any time...or it could just keep going for another 5 years...who knows? But markets tend to crash down...not up....means the velocity is always to the downside.

To the point...sometimes there are other factors to consider when weighing the importance of trends and S/R levels. But they come in handy when you need something to help you pull the trigger.

I would advise against trend lines... There is nothing objective about them. Ask 10 people where their trend line is on stock ABC and you will get 13 different lines... Always look at support and resistance with whole/half dollars. Draw a line across an area that the stock keeps bouncing off of, or topping out at. Now what $ can the stock not stay below or above. This is the support or resistance to go off of.