Find the value of array in map

Nope, that is not the correct way to do it (if I got you).
Namely, he type of the map is incorrect, it should store an array of int16_t (instead of a single int16_t). I'm showing you a working example

#include <cstdint>
#include <iostream>
#include <array>
#include <map>

using namespace std;

constexpr size_t ArraySize = 10;
static const array<int16_t, ArraySize> Val =
{
  0xC18, 0xC23, 0xC26, 0xC29, 0xC2C, 0xC37, 0xC3A, 0xC3D, 0xC40, 0xC4B,
};
static const array<int16_t, ArraySize> Val_ =
{
  0x040, 0x043, 0x046, 0x04A, 0x04D, 0x050, 0x053, 0x056, 0x05A, 0x05D,
};

using  fruit = std::map<std::string,  array<int16_t, ArraySize > >;

static const fruit red=
{
    {"step1", Val},
    {"step2",Val_},
};

int main()
{
    std::string step_;
    size_t b;

    cout<<"enter step"<<endl;
    cin>>step_;
    cout<<"enter number"<<endl;
    cin>>b;

    auto it = red.find(step_);
    if ( it != red.end())
    {
      cout << hex << it->second.at(b) << endl;
    }
}