Could you please help me put this sentence together

People could be at a borderline into having a stroke or even having heart problems, which is some reason peoples arteries could be getting clogged up, is because of what most people eat which is fast foods, and lack of exercise.

Now it's your turn. Get rid of the extra words and write this in two sentences. I'll be glad to check your answer.

People could be at a borderline into having a stroke or heart problems.

Some reasons peoples arteries could be getting clogged up, is because of what most people eat, which is fast foods, and lack of exercise.
Thank you

Good. Here are a couple of minor corrections.

People could be at a borderline between having a stroke or heart problems.
Some reasons peoples' arteries could be getting clogged up is most people eat fast foods and don't exercise.

Certainly! Here's how you can rephrase your sentence:

"The reason why people's arteries could be getting clogged up and they could be at a borderline into having a stroke or even heart problems is due to their dietary choices, mainly consuming fast foods, as well as a lack of exercise."

To put the sentence together, you should consider the following structure:
1. Start with the main idea/topic of the sentence: "The reason why people's arteries could be getting clogged up and they could be at a borderline into having a stroke or even heart problems..."
2. Provide the cause or explanation: "...is due to their dietary choices..."
3. Elaborate on the specific dietary choices: "...mainly consuming fast foods..."
4. Add another factor contributing to the problem: "...as well as a lack of exercise."

By following this structure, you can create a cohesive and well-constructed sentence.