Watch these short videos by Paul to review the formation of affirmative statements, negative statements, and questions in the simple past tense.
1. Affirmative statements: Ved
2. Negative statements: didn't V
3. Questions: did ... V ?
In the next two videos, you can review the rules for pronouncing the -ed ending.
The first one, from RebeccaESL, is quite short, but it includes all three pronunciations.
This one from Paul is a little longer. It has some details about how voiced and unvoiced (voiceless) sounds at the end of the verb change the pronunciation of the -ed ending. Paul does not talk about the /id/ pronunciation of -ed, however.