how to import to data to map using csv file?

We do have an importer that allows CSV, but we haven’t clearly given information on how to format it in our docs yet: https://www.mapster.me/wp-mapbox-gl-js/docs/import-export/importing-to-map-creator/

Your best bet will be to export a geoJSON from a map to see the format, and then format your CSV into geojson form and upload it.