Security issue

1. Currently the admin panel url open in https://ias.riceeducation.in/wp-admin/  but we need To change (wp-admin) from this url.
2. No security plugin is used. Need to use security plugin.
3. No capcha is in the login.
4. Also capcha need to use in the front-login / register from
5. They are using default DB prefix (wp_) .For security need to change that DB prefix.