Using mtl info in fragment shader in OpenGL for texture mapping

Question

In my program I load .obj model. Now I want to make a use out of .mtl for my model. I have parsed all the attributes (including texture filename - actually I just want to map a texture to my model). And I guess the lighting and texture mapping will be done in fragment shader. But I'm very confused, how do I pass all the material info to my shader?

I have a struct MaterialMTL with all the values, but idk how to it save in vbo. Maybe I have to make a vector of all the materials I have parsed from .mtl, and save the index in my Mesh? But I still have no idea how to pass all the attributes to my shader, and also how do I know if I have to use a specific material for the current fragment or not, I have one Mesh for my model and what if I want to use a material for specific fragments only...

I couldn't find any information about using mtl in OpenGL even just to map a texture, so I would really appreciate any help!

Here is a part of my code:

void drawMesh(struct Mesh m) {
    glBindVertexArray(m.vao);
    glDrawArrays(GL_TRIANGLES, 0, m.vert_count);
}

Mesh initMesh(const char * path)
{
    Mesh m;
    vector<vec3> vertsBuff;
    vector<vec2> textBuff;
    vector<vec3> normBuff;
    MaterialMTL material;
    loadOBJ(path, vertsBuff, textBuff, normBuff, material); //So here I'm parsing my obj model with the mtl file (I want to have only one material to start with)

    glGenVertexArrays(1, &m.vao);
    glBindVertexArray(m.vao);

    glEnableVertexAttribArray(0);
    glGenBuffers(1, &m.id_vert);
    glBindBuffer(GL_ARRAY_BUFFER, m.id_vert);
    glBufferData(GL_ARRAY_BUFFER, vertsBuff.size() * sizeof(vec3), 
        &vertsBuff[0], GL_STATIC_DRAW); 
    glVertexAttribPointer(0, 3, GL_FLOAT, GL_TRUE, 0, NULL);

    glEnableVertexAttribArray(1);
    glGenBuffers(1, &m.id_text);
    glBindBuffer(GL_ARRAY_BUFFER, m.id_text);
    glBufferData(GL_ARRAY_BUFFER, textBuff.size() * sizeof(vec2),            
        &textBuff[0], GL_STATIC_DRAW);
    glVertexAttribPointer(1, 3, GL_FLOAT, GL_TRUE, 0, NULL);

    glEnableVertexAttribArray(1);
    glGenBuffers(1, &m.id_norm);
    glBindBuffer(GL_ARRAY_BUFFER, m.id_norm);
    glBufferData(GL_ARRAY_BUFFER, normBuff.size() * sizeof(vec3), 
        &normBuff[0], GL_STATIC_DRAW);
    glVertexAttribPointer(1, 3, GL_FLOAT, GL_TRUE, 0, NULL);

    m.vert_count = vertsBuff.size();
    return m;
}