Bonus questions : Would my father give me anything as a ''parting'' gift like an horse or a set of armor ? How common would my circumstances be in the holy roman empire and europe ?
This is a great questions and I'm hoping that we can see some additional responses in this thread. While we wait, you may want to check out this top level response from u/Knight117 and their follow up responses: https://old.reddit.com/r/AskHistorians/comments/2a0xxn/what_would_the_second_third_and_fourth_sons_of/
Follow up question: How many such sons would have filled out the various European mercenary and crusader armies?
Provided the son in question does not/cannot afford to enter seminary and become ordained, what other life paths were available?