I have windows 8 in my pc so how can I create my problem set 1 in c language. Can I use turboc? I have download cs50 but it gives An error in function GetFloat. Plz help.
Better to avoid TurboC, its the worst thing I have ever noticed in my life, even if you were free to choose the standard yourself, avoid TurboC/C++, get to c99/gcc/g++.
First of all, CS50 does not use Borland, it uses C99. Another important thing, it seems that you haven't heard about CS50 appliance. You need to install it on your machine, it has been designed to lower your installation works. Moreover, you require it as the course proceeds for further psets.
Coming to your specific problem,
GetFloat() would not be recognized because it is not a part of standard library in C. It has been created/added separately by the CS50 staff to provide specific functionality. This means that if you aren't using CS50 appliance, then you need to install those libraries on your system. Here is one solution to compile it on other linux distro(s), if you are windows user, then problem still exists.
In short, it is better to get CS50 appliance installed on virtual machine.
you will use gedit in the cs50 appliance.
https://manual.cs50.net/appliance/2014/#how_to_install_appliance there're more information in the pset1 specifications.