How can I atone for quoting parts of other people's research without permission, knowing that this is my only profession?

Permission is not required to quote from the works of others; rather, it is required to attribute statements to their original authors. If statements are attributed to their authors, there is no harm. If they are not attributed, then the expiation for this is repentance and reissuing the research with proper attribution. As for working with certificates and the money earned from them, there is no objection to it, as the forbidden aspect lies in breaching academic integrity in transmission if statements are not attributed. However, if the research of others is attributed to oneself, then the certificates and working with them are forbidden.