How to get number of entries from a lua_getglobal and name of entries in c code

Question

I would like to know if there is any way for me to get the number of entries in a lua_getglobal and get the name of each entry

I need to know why I need to use a loop to apply lua definitions in my C code:

example moon code:

Mytbl = {
    var = {
        active: true,
        ...
    },

    inv = {
        active: true,
        ...
    },

    sts = {
        active: true,
        ...
    },
    ...
}

My C code:

void read_test(void) {
    lua_State *L;
    L = luaL_newstate();
    luaL_openlibs(L);

    if (luaL_loadfile(L, "test.lua") || lua_pcall(L, 0, 0, 0))
    {
        printf("Error 'test.lua'\n");
        return;
    }

    lua_getglobal(L, "Mytbl");
    
    for(int i = 1; i < GlobalEntry; i++) {
       lua_getfield(L, lua_gettop(L), get_tablename);
       lua_getfield(L, lua_gettop(L), "active");
       p->active[i] = lua_toboolean(L, lua_gettop(L));
       ....

    }

    lua_close(L);
    printf("Read complete.\n");

}

What is defined in the C code as GlobalEntry would be the function to get the amount of entries from lua_getglobal

And what is defined as get_tablename is the function that will get the name of the entries

Is there any lua function that allows you to do this?