Hello,
1) Slider issue is related to Stripe plugin http://prntscr.com/ibyq4g js error breaks all the other scripts. Contact plugin author to solve the problem.
2) http://prntscr.com/ibyqmn you have chosen the small layout for the single product in the product settings. It overrides the global Theme Options. Set to inherit to use settings from global Theme Options.
3) To remove Additional Information tab follow the WC documentation https://docs.woocommerce.com/document/editing-product-data-tabs/
Regards