Bring up different info boxes for each marker on the map after clicking on it

I'm trying to make an interactive map with markers, that would bring up a box with information about the place. I'm using MapBox API and I managed to add a marker using GEOJSON

var geojson = {
  "type": "FeatureCollection",
  "features": [
    {
      "type": "Feature",
      "properties": {
        "marker-color": "#7e7e7e",
        "marker-size": "medium",
        "marker-symbol": "",
        "name": "zamek"
      },
      "geometry": {
        "type": "Point",
        "coordinates": [
          17.968410551548004,
          49.47832705255177
        ]
      }
    }
  ]
}

Now I need to assign an event to that marker that would bring a text box specific for the place of the marker. I don't have any experiences with Js, I'm basically learning in this process.

So what would be the best way to do it? My info box would be a div that would "slide in" from the left side of the screen (its a div with 100% height and 300px width placed on left: -300px) with appropriate information. My only idea was to use some kind of database (it may be a total non-sense since I'm just a noob) with all the titles, texts, etc . and change the info box content based on which marker was clicked on.

Example: If I click on the castle, the website pulls the necesseary text from database for a "castle", puts it in the info box and displays it.

I would really appreciate any help with this, as I said, I've just started studying the magic of interactive web making and js so please correct any non senses I've said in this (also I know my english isn't by any means good, so please don't blame me).