Then you need to learn arrays and pointers, might take hours.
char buffer[ 12 ]; // allocates 12 bytes as type char, pointed to by char *buffer.
That's right, buffer above is a pointer. Every array name is a pointer (add dimensions and it's a double, etc, pointer).
Syntax
Serial.write(val)
Serial.write(str)
Serial.write(buf, len)
So you want to use the last one.
Serial.write( toCCS(float value), 4 ); // that should probably do it but don't bet the farm