Hello, where are the different points of interest? are they accessible by car? Or is there shared parking with shuttle relay?

There are routes not accesible in Winter. You have to check online.

Yes, accessible by car. No shuttles. Use maps and read carefully to find spots. There are many groves of giant sequoias.

Only central poi is the trail of the 100 giants , this can be reached by car

Mitchell Peak is pretty good. But you need a powerful car to get up there.