How should one who has fasted Ramadan for many years but used to lie, not perform ghusl for janabah, or pray without purification, make up for these? Is he required to make up for 10 consecutive years, and is it permissible for him to make up two separate days a week to alleviate hardship?

Lying is generally forbidden (haram), and it is even more forbidden for a fasting person. However, it does not invalidate the fast. It is also not obligatory for a fasting person to remain in a state of ritual purity (tahara) at all times, nor does their fast become invalid if they wake up in a state of major ritual impurity (junub). If you avoid the things that break the fast, then your fast is valid, and you are not required to make it up (qada'). However, if you commit something that invalidates the fast, you must make it up, and it is not a condition that the make-up fasts be continuous. You are required to pay an expiation (kaffara) for delaying the make-up fasts for each day if the delay was intentional and you were aware of its prohibition. However, if it was due to forgetfulness or ignorance, then you are only required to make up the fasts.