Do you think humanity will ever create colonies on the other planets (not just couple of trained astronauts but a civilian population in a city or something similar) and depending on your opinion why not / where and when do you think they're likely to be created first?... also will the frontier of colonising be in our own solar system on Mars for example or on some exoplanet
The purpose of going on mars for these astronauts is to make it ready for colonization. Plan is organised and I think that it is pretty much possible.
I don't think that is so.
There are various reasons this idea exists.
One is to make money from government contracts for Elon Musk.
Another is political status for countries that pay to play.
In a practical sense, "making it ready for colonization" would require hundreds of rockets with payloads of machinery and robots. Sending humans is NOT an essential part of making it ready for colonization.