What should a person do if he committed the secret habit twice after the first stage of exiting ihram in Hajj?

He wants to do ‘umrah and has some questions about ihram

Is it permissible for a woman in ihram to put something under her khimaar (head cover) and let it fall over her face?

Ruling on wearing ordinary clothing over the izaar and rida’ [ihram garments] before starting the rituals

He stayed in Makkah for six months after Hajj, then he went to Madinah; does he have to do tawaaf al-wadaa‘ (farewell tawaaf)?

He halted in Muzdalifah and did not complete the rituals of Hajj

She covered her face during ‘Umrah due to lack of knowledge; what does she have to do?