there are 3 tenses Past, Present, Future
Google Translated
他踢足球(过去式)He played football (past tense)
他踢足球(现在时态)He plays football (present tense)
他是踢足球(将来时)He is playing football (Future tense)
When you are using past tense it means that it has already happened, it's already been done.
I hope this helps a little because i don't really understand your question