The two passages establish six key points: make-up for an invalidated commenced voluntary fast; make-up for an invalidated commenced voluntary prayer; distinct assessment of excuse and obligation; abstention after puberty or conversion during the day; obligatory fasting on later Ramadan days; and no make-up for the earlier time or the current day under the principal Hanafi rule.
The next passage begins “wa-man ughmiya ʿalayhi fī Ramaḍān” and discusses unconsciousness, recovery and subsequent circumstances. It belongs to the next level.