All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
All praise be to Allaah Who guided you to the straight path and enabled you to repent from those evil deeds because abandoning the prayer, invalidating the fasting and masturbation are forbidden, especially abandoning the prayer. Some scholars are of the opinion that abandoning the prayer even though one acknowledges its obligation takes a person out of the fold of Islam. However, a person who abandons the prayer is not ruled to be a non-Muslim and he is not treated as such unless the evidence is established against him, but the majority of the scholars are of the opinion that abandoning the prayer while believing that it is an obligation does not take a person out of the fold of Islam. For more benefit, please refer to Fatwa 85264.
As regards the issue of making up the missed prayers that a person missed deliberately, some scholars are of the view that whoever abandons the prayer deliberately should not make it up, while the majority of the scholars are of the view that it is an obligation to make it up, and this is the preponderant opinion in our view in Islamweb.
Therefore, you should make up the prayers that you missed including those void prayers which you performed while in a state of impurity. If you do not know how many prayers you have missed, and how many fasts you invalidated because of masturbation, then you should make up as much prayers and fasting as you predominantly think that you are acquitted from liability; for more benefit, please refer to Fatwa 83727.
However, you are not obliged to expiate for the days of fasting which you invalidated due to masturbation; you are only obliged to make them up and repent. For more benefit, please refer to Fatwa 89038.