Investing means you are swinging trades/options/stocks for future usage/benefit similar to a 10 years insurance payout. Normally investments are for those stable long-term blue chip companies.
Gambling is like betting on something that the payout probability is very low (like lotto, 4D, Toto, casino games). Revenge trading or lotto trading is also counted as gambling.

Hopefully some day this message will be read by my son. There are so many points to convey, but i will limit down to three most important points (personal opinions)
First and foremost, i would like to tell him that investing is not gambling unlike what other people or older generation thinks. Personally i regretted that i didn't start early due to pressure from family, and now i do not want the next generation to make the same mistake.
Secondly, I would like to teach him that losing money is part and parcel of investing; there are always ups and downs in volatile market. Always take the loss as a case study and try to learn from the mistakes made.
Thirdly but definitely not the last. Invest at your own appetite, and do not follow blindly with others. Do not worried about Fear Of Missing Out (FOMO) on stocks, but instead live life happily.
As long as profits are made and no matter how big or small, one should be satisfied!
This is my humble message to my son and of course to everyone who is willing to read 😁
Cheers and happy investing!...