How to cast from a const struct to a struct?
typedef struct user {
    char name[MAX_NAME]; // name of a user is an array of max 32 chars
    char profile_pic[MAX_NAME];  // This is a *filename*, not the file contents.
    struct post *first_post;    // pointer to the user's first post, which will contain 1) a pointer to the post itself and 2)  a .next attribute, that will in turn point to another post which will be stored in the linked list of posts of the recipient of the post
    struct user *friends[MAX_FRIENDS]; //Points to another user
    struct user *next;
} User;

User *find_user(const char *name, const User *head) {
    
}
