Sometimes after writing a manuscript, I get confused as to where to submit it for review and publication. Navigating between Paid-journals and Free-journals, which one should be more considerable for a research paper to be submitted?
I think the "impact factor" or other measures of citation frequency should be your first concern. This indicates how likely it is that other researchers will actually use your article in their own work. Beyond that, free journals increase the access of other researchers to your work -- but they aren't really "free" since you usually have to pay to get your work published in that kind of journal. So, your resources also matter in this choice.
At times some of the free journals have higher impact than the paid ones, check for an appropriate journal where you will be able to get to your audience. Your own h-rankings is number of citations of your articles. So you need to consider a number of factors.
It's all about the quality of your work, and your objectives with your research. If your research is of Good Quality and high significance, it may be accepted by good journals. However all good journals shouldn't be necessarily paid, and nor all paid journals are necessarily good.