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, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
The wise Sharee'ah conditioned ability for liability for religious obligations. Allaah Almighty says (what means): {Allaah does not charge a soul except [according to] what He has given it.} [Quran 65: 7]
It is also one of the well-established principles of the Islamic jurisprudence that hardship brings ease and that the more difficult a matter grows, the easier it becomes.
Consequently, as long as your father is as you mentioned, if he can make Wudhoo’ and pray, even through somebody's help, he has to do so. If this leads to unendurable hardship, he is allowed to make Tayammum (dry ablution). He has to remove the impurity and cleanse himself properly as longs as it is not difficult to do so.
As for prayer, he is permitted to perform prayer in the state that is possible for him. He can pray in the masjid, unless he pollutes it or harms others. In the latter case, he has to pray at home.
Allaah Knows best.