after few tries on how to make sideway garage tutorial, i finally made it. but, i have one problem. i made a house using the cement garage (the gray one) at first, then i realized that i wanted to use the brick coloured garage driveway,but it was too late.i only made it few.but not on the entry drivemway. how to undo it? i tried move objects off and remove the tile,bla bla..but garage was still on the sideway, not the normal way.

Hmmm... I'm not sure I understand what you're asking.
Do you want to change the interior garage floor extension piece to brick?
Or, do you want to change the exterior driveway to brick?
Do you want to get rid of the sideways driveway extension piece and replace it with the original type?

Can you provide a picture to help us determine exactly what you want to do?

oh yes..the exterior driveway...should be the brick.i just found the screenshot..so i'm going to post in here. and yes..i also want to exterior driveway to be normal like before because i everything i did, the driveway didn't turn to normal.maybe because i've saved the game..oh no...

maybe try and use the rotate 45 degrees cheat

You could just download the invisible driveway, then use floortiles to recolour