(1) If she wants to embrace Islam wholeheartedly considering Islam as true religion, then take her to any nearer madrasa and make her recite the kalmiah. Also, teach her Talimul Islam, Bahishti Zewar etc or if you do not know you should learn it first by any alim and then get her learn it. Ask her to know how to offer salah and memorize some surah by heart.
(2) Today’s Christians and Jews are generally atheists, they neither believe in God nor prophet; therefore it is unlawful to marry such Christians and Jews without their conversion to Islam.
(3) You should also repent to Allah sincerely and have firm intention not to repeat the acts in future, in-shaAlah your sins will be purged away. We should not lose hope in Allah’s mercy, since those who lose hope in Allah’s mercy are infidels. The hadith also says: ?the mercy of Allah overcame His wrath.?
Allah (Subhana Wa Ta’ala) knows Best
Darul Uloom Deoband