You know of a site is credible if it has a .org .edu or .gov. Stay away from blogs.If it is on the school website it is a good source. If there is adds it is probably not a good cite to be using. Try to use websites recommended by teachers. Also double check to make sure the same info is on many cites
Plagiarism and how to avoided it.
I admit I've plagiarized before when I was little. Plagiarism is not OK and is a criminal act. In school or collage it will get you in major trouble. To avoid plagiarism cite your sources and paraphrase. DON'T COPY AND PASTE UNLESS YOU USE QUOTES . Only ten percent of a peace need to be quotes. Summarizing is OK but you still need to cite.
Keywords are important when you want to search up a research topic. EX If you do China don't type Pokemon just type China