1) Secondary account holder cannot use their CC to get Spend bonus, as per OCBC 360 info page: https://www.ocbc.com.my/personal-banking/accounts/360/#divd3

You and your wife jointly open a 360 Account
You are the primary accountholder
You and your wife are Principal credit cardholders

✅Only Credit card spend by you (primary accountholder) and your son (supplement CC from your CC) will be recognised
❌Credit card spend by your wife (secondary accountholder) will not be recognised





however OCBC Malaysia have not been accepting any new credit card applications from last year's MCO (see #3)

2) Yes, through Transfer Funds > Other Bank's Account > Credit Card Payment. Qualify for "Bill" bonus.

3) OCBC based in Malaysia actually not accepting new-to-bank credit card applications for now, last I checked (December 2020), so if you want the Spend bonus you need to get Debit+ATM card. They might have changed policies recently but I would note that I've received zero advertising material for credit cards, so they're most likely still not accepting new application. You may enquire their branch/hotline to check.