You can add sources of base map data to your Mapbox maps as well, such as from Stadia Maps, OpenStreetMap (JSON style), Carto, and others. You will need to find the style JSON endpoints from these base map providers, but can insert them as a source on your map by creating a custom variable:
const basemap =
"https://raw.githubusercontent.com/go2garret/maps/main/src/assets/json/openStreetMap.json";
const map = new mapboxgl.Map({
container: "map", // container ID
style: basemap,
center: [-122.169462, 37.429889], // starting position [lng, lat]. Note that lat must be set between -90 and 90
zoom: 13, // starting zoom
});