Why are these words not appending in C? - c

Question

I'm trying to write a function in which two words are appended into a third string, and this function must use malloc(). I'm first writing it in the main before I put it in a function. I have:
int main(void){
char *word = "Johnny";
char *word2 = " Boy";
char *buff = malloc(100 * sizeof(char));
printf("%d\n", sizeof(buff));
int ct;
for(ct = 0; ct < strlen(word); ct++){
buff = word;
}
printf("%s\n", buff);
printf("the counter is now %d\n", ct);
buff += ct;
for(ct; ct < 13; ct++){
buff = word2;
}
printf("%s\n", buff);
}
I want buff to say "Johnny Boy" but at the end of it, "Johnny" is overwritten, and it just says " Boy"

Answer 1

Listen, while we want to help, SO is not really meant to be a classroom environment. Plainly, you're struggling with a fundamental lack of understanding about pointers / string manipulation in C, which is very basic material. Get a BETTER book on C and compare this code to your work, and study on it until you understand the differences and exactly what's being done at each step.
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main(void){
char word[] = "Johnny";
char word2[] = " Boy";
char *temp;
char *buff = malloc(32 * sizeof(char));
if (buff == NULL) {
puts("allocation error");
return 1;
}
for (int ct = 0; ct <= strlen(word); ct++) {
buff[ct] = word[ct];
}
printf("%s\n", buff);
temp = buff + strlen(word);
for (int ct = 0; ct <= strlen(word2); ct++) {
temp[ct] = word2[ct];
}
printf("%s\n", buff);
free(buff);
return 0;
}

Answer 2

Okay. The first problem here is you must understand that strings are arrays. You cannot in c say that an array is another array. To be honest there are a lot of problems with this code. The guy above me's code is probably gonna be pretty complicated for you to understand so I will try to give you some more understandable code. One more thing, I won't be using pointers because I haven't mastered them yet.
#define BUF 255
int main( void)
{
char word1[BUF], word2[BUF], word_full[BUF];
int ct, length;
printf( "Input your first word\n" );
scanf( " %s", &word1);
printf( "Input your second word." );
scanf( " %s", &word2);
length = strlen( word1 );
for ( ct = 0; ct < length; ct++ )
{
word_full[ct] = word1[ct];
word_full[ ct + length ] = word2[ct];
}
word_full[BUF] = 0;
printf( word_full );
return 0;
}
return 0;
}