Very nice; everything was understandable. I mostly combined sentences to avoid fragments and to make the text flow more logically. The phrases in parentheses are OK, but are either superfluous or simply less native. Keep up the good work! Elderly people they often eat lighter. In the morning and evening (or "in the morning and at night"), they usually eat porridge, and more vegetables (of course). On the other hand, young people like me prefer to eat what we like, (such as) meat 🍖, spicy food, and junk food. I'd like to live a more healthy life (or "a healthier life"), but it’s hard (for me to do it).

For older people, they often eat lighter meals. In the morning and night, they usually eat porridge with more vegetables, of course. On the contrary, for young people like me, we prefer to eat what we like. Meat 🍖,spicy and junk food. I agree it is important to lead a healthy life. But it’s hard for me to do it.

For the elderly they often eat something light/ eat food with a light taste(吃清淡口味的菜)/ eat less(吃得少). In the morning and at night, they usually eat porridge(alternative: They usually eat porridge for breakfast and dinner). They also eat more vegetables. On the contrary, the young people/generation, like me, prefers to eat what we like, such as meat 🍖, spicy food, or junk food. I agree with a healthy life, but it’s hard for me to do it.