Should I help my parents invest their money if they ask me to do so?

If I were to do that, I will make sure I have enough money to return to them (capital guaranteed by me) if the investment is giving negative return. I don’t want them to worry about money at this kind of age when they supposed to enjoy their golden age. That’s how I will do it.

You can help them, then You must be excellently informed.

The better choice would be to involve all of Your family.

Also an independent investment advisor (based on honorary fees) could be an option.

The mainstream bank/insurance advisors often are biased by pressure/incentives from their companies...

Investing for others will train you to be especially more mindful in your decisions given how the money belongs to someone else you know. You aren't accountable to yourself but rather to others. I think it'd be good experience to invest a small sum first and see how it goes and grows (hopefully)

If you want to do the investment management for them, ensure that you have the revelant MAS license to do so.

Alternatively you may engage a licensed robo-advisor/digital-advisor or a licensed financial advisor to invest on their behalf.