I am currently using StashAway as my main investment. I wish to try stocks/ETF index funds, any suggestions on where I should invest?

For picking of selected ETFs, you can try kristal.AI which gives you 25 free trades(include both buy and sell orders) per calendar year. There is a FX conversion fee of 0.05% when buying in ETFs that are denominated in foreign currencies.

If you want access to US stocks, HK stocks and SG stocks as well as ETFs in the abovementioned markets, you can consider opening a FSMone account for a start. Funding is easy and instant via Paynow, therefore no transfer fees. Transaction fees are around $8-$10 per trade.

With regards to where you should invest for a start, I think you can look at S&P500 ETFs like IVV, VOO. To capture as many markets as possible around the world, you can look at IWDA. Once you get an idea of your investment strategy on which sector or geographic region you want to foucs on, you can then pick ETFs that are narrower in scope.​​​