If you just want bones https://www.kinebody.com/new/webapp/index.php will do. For muscles and bones this might help. https://anatomytool.org/interactive?f[]=field_anatomical_structures%253Afield_as_anatomical_system%253Aparents_all:709

There’s this website https://figurosity.com/ that has 3-D models of all sorts of poses. You have to pay to see just the muscles though and you can’t make your own poses