Hello,

1. Instagram does not have the option to share by its nature.

2. Configure your [social_buttons] shortcode in the Theme Settings > Social networks. You can leave the field empty to remove a particular link. Note that there are two types of social buttons. First one is SHARE buttons [social_buttons type="share"]. It displays icons that share your page on social media. And the second one is FOLLOW buttons [social_buttons type="follow"]. Simply displays links to your social profiles. You can configure both types here.

Best Regards