[Map] How do I select an area in Advance Map Editor?

I've literally looked all over via Google and haven't found ANY tutorials that would explain how to do this. I've seen people do it in videos, but they don't say how they do it, they just randomly *poof* select an area like a 3x3 and paste it in like a normal tile. I've managed to do it accidentally before but I cn't figure it out. I'd also like to know how to fill an area automatically - something I've also seen in videos before. Thank in advance for the help!

Hold Crtl+Right click and then pan over the tiles you want to copy and paste, left click to place them. As for filling an area with a single tile, press the middle mouse button.

Holy crap thank you! I've been looking so long to find this information! :D