How should a person who is afflicted with continued major ritual impurity (incontinence of urine, bleeding outside the monthly period) perform ablution?

Such a person should make ablution for every prayer after its due time and after removing impurities from their body and outfit, and should place a fresh diaper whenever needed so as for the impurity not to spread out. They should also perform prayer immediately even if incontinence of urine continued, and should repeat the aforementioned for every obligatory prayer, then perform optional prayer as much as they want.

Is buying shared land from someone who has taken possession of it considered halal or haram?

The shared land is possessed by the country i.e. for all people; therefore, it shouldn't be possessed/occupied save by it's guardian/owner permission,thusly it can't be possessed save by having owners' permission. Finally, buying it from a person who don't possess it is impermissible. And Allah Knows Best.

Is it permissible for the young woman to turn the suitor down if she had no feelings for him?

Yes, it is permissible for her to do so.

I had my menstrual period at the beginning of Ramadan for six days, then it ended and I became pure. After four days, I started noticing some blood again, which has lasted for two days now, but it is not as heavy as menstrual blood. Is this blood considered menstrual blood, and what is the ruling regarding my prayers, fasting, and reading the Quran during this period?