Ok, in your location it's a few magnitudes harder. Diversity in Europe is low. There's a lot of websites that offer identification guides. For plants, AI apps have become crazily good. I still think you should be able to identify most wildlife you see in a city even in Singapore. Remember 90% or so species are so rare that you probably will never encounter them. The fact that you stumble across them in an urban environment already means that they are most probably very common.

Another relatively rare guest I have never seen before in my life, not ultra-rare but clandestine. One of very few plant-hoppers we have in Europe. About 1 cm long. Apparently it's not even an invader from the South but occurs all the way to Scandinavia. Every time you find something new, you also learn something new.