Hi @medhanlee0721
Have you taken a look at our youtube channel?
We have multiple videos going over trimming and truncing with dada2 in QIIME 2 that might be helpful for you.
I just wanted to jump in here with a friendly reminder that your work is your own. We cannot provide you with trim/truncation lengths for your data, as that is something that you must determine in your analysis.
With that being said, the videos on our Youtube channel that @cherman2 mentioned do discuss trim/trunc lengths based on quality scores, which is how I'd recommend you make your decision. Another great resource that discusses quality score based filtering using DADA2 is our Moving Pictures tutorial, which I'd recommend going through (if you haven't already).
One final resource I'd recommend is searching for 'selecting trim/trunc length in DADA2' on the forum - you'll find many threads regarding the same question that discuss how to make an informed decision on these parameters based on your interactive quality plot.