Hi, u/Edmure.

In additional to Panda's suggestion, I would also recommend this post:

"I'm a medieval Lord who has just been called to arms by the King in defense of the realm. How do I go about assembling my army for campaign? Where would I start? What quality can I expect my troops to be?"

This covers mainly the first question.

Both u/SoloToplaneOnly and u/Knight117 answers there are great. Knight's focuses on England in 1346, so that may be of interest to you.

Well in medieval times all soldiers were responsible for their own arms and armor. Theoretically a peasant could equip himself in the fashion of a man at arms or knight, but this would be prohibitively expensive and was almost never seen. This is a bit later than 1100 but in 1181 King Henry II issued a famous proclamation known as the Assize of Arms, which obliged all freeborn men to bear arms in service to their king and the realm (on pain of “vengeance, not merely on their lands or chattels, but on their limbs"). The assize stipulated precisely the military equipment that each man should have according to his rank and wealth. The assize effectively revived the old Anglo‐Saxon fyrd duty and established restrictions on weapon ownership by Jews. Every knight was forced to arm himself with (at minimum) a coat of mail, and shield and lance; every freeholder with lance and hauberk, every burgess and poorer freeman with lance and iron helmet. This universal levy of the armed nation was wholly at the disposal of the king for the purposes of defence. ... By his Assize of Arms Henry restored the Ancient Anglo-Saxon Militia System, and supplied the requisite counterbalance to the military power of the great feudatories, which, notwithstanding the temptation to avoid service by payment of scutage, they were still able and too willing to maintain. Interestingly this early proclamation is where the concept of all freemen having a right to bear arms originates from.