Basically you did through their trash. You can learn from animal bones what food they ate. You can learn from broken or whole pottery what they ate and what art they liked. You can find broken weapons or artifacts.
There is no Hindu Arabic writing. The two cultures used different scripts which are non-compatible. One of the major differences is that Hindu writing goes from left to right whereas Arabic goes from right to left.
it does not help you learn about different cultures
Objects from the cultures
There is no known western culture whose writing system runs in any direction other than left to right. In fact, The latin, greek, and cyrillic alphabets combined make up the vast majority of all writing systems on the planet, and they are all left-to-right.
Writing
writing
Most people can learn automatic writing, however it is hard.
they were the first ones to figure out writing so they did it
If you speak Greek you can read it ... you have to learn it the same as you learn any writing.
Written scripts evolved with the medium used for writing. Medium like paper,leather,bark,palmleaf used dye or liquid ink written with a stylus or pen from left to right so that the words were not smugged by the palm/ arm which moved in the unwritten part of the medium.
The best way to learn about other cultures is to immerse yourself in the culture. Move there, live there, learn the language(s) and experience the every day over an extended period of time. The above is true, but if you aren't financially able to do this then read everything you can on different cultures or at least one in particular you are interested in. Also choose friends of different cultures and you can learn some of their traditions and they can learn yours. Variety is everything in friendships.
In some cultures, it is considered impolite to eat with your left hand because the left hand is traditionally associated with tasks considered unclean, such as using the bathroom. Eating with the left hand is seen as disrespectful and unhygienic in these cultures.