Where can I get a map for the trail I’m planning on going up also is there a topographical map for the area so I can see elevation

You can make your on map use Caltopo website. It's has several tools to suit your needs. It's free for use and you can print your map, but it's low-res. If want higher resolution for printing there is a fee option. You can also export your map to Google Earth and other map apps. https://caltopo.com/map.html

I use viewranger. It's an upside down hike meaning you hike down then have to return up. At the main road it's about 3450ft and at the falls it is about 2900 ft. If you can find parking at the bottom that cuts off a good chunk of that. On viewranger it follows Switzer Truck Trl.