Here the word "we" refers to Peter and the other apostles, but not to his readers. Alternate translation: "For we apostles did not follow cleverly made-up stories" (See: [[rc://en/ta/man/translate/figs-exclusive]])
These two phrases may refer to the same thing and be translated as a single phrase. Alternate translation: "the powerful coming" (See: [[rc://en/ta/man/translate/figs-hendiadys]])