Is it permissible for an elderly sheikh to perform tayammum for both minor and major ritual impurity (al-hadath al-asghar and al-hadath al-akbar) when water is available, if he is unable to perform ablution or ghusl due to overwhelming flatulence and inability to repeat ablution, or inability to perform ghusl from janabah?

Water must be used for Wudu' (ablution) and Ghusl (ritual bath) from Janabah (ritual impurity), and it is not permissible to resort to Tayammum (dry ablution) unless there is a legitimate excuse. If the Shaykh (elderly person) can use water by himself or with assistance, then Tayammum is not permissible for him. If repeating Wudu' for every prayer is an unbearable hardship for him, then he may combine the prayers (Dhuhr and Asr, Maghrib and Isha) with one Wudu' for each combination, and another Wudu' for Fajr. However, if even that is difficult for him due to difficulty in movement or the unavailability of someone to provide him with water, then he may resort to Tayammum. It is not permissible to wipe the body with a wet cloth to remove Janabah; rather, he should perform Tayammum.