I am currently in NS (21) and started investing since last year. Any advice on what I should do next in my situation?

Just hold onto your existing portfolio, then divert monies to S&P 500 index for your index component

Your portfolio is very REITs heavy. Looks like you either see financial bloggers holding many REITs but do note capital size matters. REITs main purpose is mainly for income and not growth. Us being in our 20s, I believe we should allocate more to growth stocks and capture the capital gains. You should continue holding whatever you have and start to load up maybe a growth based ETF (eg VOO VTI or a higher risk higher reward ETF such as QQQ) or if you know how to value a stock and pick them yourself, Singapore does have its fair share of growth stocks but USA will be where you find the multibaggers more often then not. Just a suggestion but all these depends on your own risk appetite and personality!