When reading a scientific paper you generally do not read it in its entirety from the beginning to the end. Instead, you generally read the abstract first to get an overview of the paper and decide if the paper is relevant enough to your project to warrant further reading. If the paper is relevant you can delve into reading it but do not need to read every section in order.
Start by reading the introduction carefully – several times. There will likely be many words or phrases that are unfamiliar to you.
Generally, when first researching a topic you will need to do a careful reading of the introduction section. Introductions can be great places to find other references and to get a better understanding of the field. Mark references in the references section you want to look up later.
Skip over the methods section (unless you are interested in their particular methods or want to use a similar assay yourself).
Read over the sections of the results and look at the figures. Do the figures clearly back up the trends described in the results sections? If you are not clear on the purpose or interpretation of a figure then read the results text that discusses it to get a better understanding.
Read the discussion/conclusion if you are interested in how they tie their findings back to the larger field or which findings the authors find most important and highlight in this section.
Remember that even scientists in the field of research often have to read papers several times to fully understand them. So if you want a thorough understanding of the research you will need to reread it several times.
Here’s some more helpful info on reading scientific