Problem description: What are the common websites for downloading English sci?
Questions and Answers:
First, Google Scholar.
Second, web of science.
Third, scihub
The first two generally require logging in to the student account of your university. If your school does not have copyright, then use the third scihub.
If the above three methods don't work, you can find other students to see if their school has copyright, or ask for help from some groups for finding documents.