no more power steering

[AquaPython]

took a shit on me yesterday.
makes a wierd noise. slower speeds , turns are half-powered, to not at all, with a struggling, thumping noise / feel

i am not so mechanically inclined and did not know about changing out or flushing the power steering fluid. for all i know, unless this was done at some point during a service, this is the original fluid at about 105k.
it is a dark orange.
it was also at the low level. so i went topped it off with new , clear yellow p.s. fluid. it did make a difference. but it is still not great. do i have to flush it out, and replace with brand new? if, so how?

this is a '99 altima.