cannot upload pics and change text to web site.. needs to be fixed

i have a web site that was created with a template, a few changes were made not many.? I want to upload more pics and change text but i cant.? A coder uploaded it for me to my? domain? and when he gave me the user name and password for a program to access the site ( the program was cuteftp? ) the user name and pasword did not work and the coder has his money and is gone I need this situation fixed.