其实大概的看这两句话意思都差不多（information 不能加S,是不可数名词）
it is really difficult to learn these information in one day.
强调“学习”的过程难,不一定是信息本身难.（或许是自己水平的原因）
this is really difficult information to learn in one day
强调“信息”,说明信息本身有一定难度,自己的原因少.