That would still make him a landowner or middle-ranking servant of an aristocrat. And then an outlaw and poacher. None of that supports the argument that ordinary folks received combat training throughout their lives.
I wasn't addressing whether ordinary folks got training or not. Only your statement about the Robin Hood Legend. As for Robin Hood being a landowner the earliest ballard only state he was free which could be a lot of things. For example, he was associated with Much the Miller's son early on so he could be considered an apprentice or journeyman to a miller. The only thing consistent was he was not a villein or any other unfree status.
But the answer to that they did but the specifics ars nuanced and peasant (unfree) troops were shit in most cases. Because. their training amounted to infrequent holidays (4, 2, or 1 time a year) of drinking and eating with a little military drill on the side with the spear and other traditional militia weapons.
Feudal manorialism was big on collective responsibility. So while each serf tenant wouldn't be covered even under the lowest legal category, The serf and all his neighbors would owe the military duty of a single soldier whether they were free or unfree. The general militia existed to repel an invasion and other immediate threats. The military duty was for use by their feudal overlord for whatever purpose they saw fit although the service time was limited.
See the Anglo Saxon Fyrd, and the Assize of Arms 1181 among other things.
As time went on, most of this was converted to monetary fees with the lord hiring their troops outright. This could be a lucrative source of income for free and unfree alike. Along with the fact that the general militia was still needed for immediate threats but remained pretty much just as badly trained.
How this manifested varied a lot from region to region. Also the late serfdom of eastern Europe and Russia had it's own naunces as well.
So the general answer is yes unfree peasants got some very basic training in drill and weapons. But it was crap compared to what Knights and men at arms had for equipment and were able to accomplish with their training. But good enough that when the peasant did revolt it took a concerted effort by the king (or lords) to suppress them.