i went to school by means of riding a bicycle every day这句话如果语境是说过去就没有错误.如果是表示现在每天,那么用I go to school比较好.
还有,这句话不简洁,I go to school by bike every day就足够了.native speakers没有人说by means of riding a bike,他们会觉得很奇怪~
一般都用what I said,强调我说过了.如果说我说的是他的话,强调“他”,会说I'm talking about him(,not about her or anyone else.)