If you are a man, it is. Poland doesn’t do same-sex marriage.
The next prerequisite is finding a Polish girl who wants to marry you.
You then need to visit her family. On the last evening, when there is a big meal and you are the guest of honour, it is the time when you formally ask for the daughter’s hand in marriage. This you do after the main course but if you were given duck blood soup, a dark sweet soup called czernina as the first course, then it is a signal not to ask, as she is already intended for another nobleman.
Once these formalities are concluded the rest is easy.