Read file information and load it into a B tree struct

Question

I have the task of reading a file and uploading its information to a B tree structure, in order to develop a search algorithm to search the information by name, but my difficulty is already in the beginning, it’s my first time using this kind of tree structure and I can’t handle the same.

I believe the structure of such a tree is like this:

typedef struct { //estrutura do arquivo a ser lido
    char uf[3];
    char municipio[61];
    long long nis;
    char cpf[15];
    char nome[61];
    int parcela;
    float valor;
    int p; // posição do registro que contém a subárvore direita 
} arvb_info;

struct no_arvb {
    int m;     // número de chaves no nó
    int p0;    // posição do registro que contém a primeira subárvore
    arvb_info chaves[100]; // vetor de elementos
};

And then I’m reading the file like this:

printf("\tEntre com o nome do arquivo: ");
scanf("%39[^\n]", filename);
if ((arq_dados = fopen(filename, "r")) == NULL) {
    fprintf(stderr, "\tErro de abertura do arquivo %s!\n", filename);
    fclose(arq_dados);
    return 1;
}

If someone could give me a light or a way to carry the information in such a structure would be of great help!