As OP has already discovered, to stand on one's own (two) feet is an idiomatically established metaphoric usage meaning to be independent (usually, but not necessarily, financially independent).
But although it might seem tautologous to include both stand and feet when used "literally", it's by no means uncommon. My guess is most of almost 20,000 written instances of stand on your feet are either completely literal or nearly so (it's often used to imply Get up and do something to resolve a problem, as opposed to simply Rise from a seated position).
I would tend to draw a distinction between...
1: I've been standing on my feet all day
2: I've been standing all day
...both of which are far less common than...
3: I've been on my feet all day
One significant difference is that #2 often occurs in contexts where I've been standing around waiting for something (by implication, standing in order to be better able to react quickly when it does happen).
But another difference is that although it's relatively less common, #1 strongly implies that I've been standing in the same place all day, as a consequence of which my feet are aching. On the other hand, #3 strongly implies that I've been moving around from place to place a lot - as a consequence of which I might feel "rushed off my feet" (I'm physically and mentally tired all over, it's not just my feet that ache).
Thus #1 would be more likely from, say, a sales assistant who's been standing in one place behind a shop counter serving customers. #3 seems more appropriate for, say, a postman who's been walking all day, delivering the mail.
But #2 has neither of those implications, and it may be useful to note that I've been been standing here all day is actually more common than the simpler version in my numbered link above. And in the vast majority of cases it's not really "literal" at all - there's usually an implicit or explicit reference to either standing around waiting or doing nothing in particular, just standing around idly.
For the literal sense in imperative contexts, you're more likely to hear Get [up] on your feet! from a speaker urging his audience to rise from a seated position (assuming feet are to be referenced at all).