planed task date and actual task date

Im new ms project user

I created a project with a task list with dates and time for each task .

I want to Monitor, actual date and actual work time for each task and to see if I planed the times and the dates right.

But when I add actual time and actual start to MS project it changes the original time and date I gave for the task

i want to have both details , my planed details and actual details

Any ideas ? Thanks !