If আপনি want to look yourself just type in গুগুল "free trial Microsoft power point" It isn't really possible to download Microsoft Office software for free anywhere. but, আপনি can get a free 60-90 দিন trial easily.
The first link is just powerpoint. The 2nd is The complete Microsoft Office 2010.
আপনি can't just download Microsoft Office, It's not like firefox. আপনি have to buy it. I recommend Microsoft office 2003, It may be a little outdated but it's easy to use and it would be a lot cheaper than getting the latest version.