Yes, provided the inputs in question are line inputs. Since I’m not familiar with your amplifier, I can’t tell you any more - check the specs.
As for the cable, shouldn’t that be fairly obvious? You’ve got 2 TRS outs L & R, and your amplifier has 2 RCA unbalanced inputs. Although the UR22 outs are balanced, you can also use them unbalanced ,so you’d need a cable with 2 male TR Phone jacks at one end (because you don’t need balanced jacks) and two RCA males at the other end. The length you’ll have to figure out yourself, just keep in mind this is a “stereo adapter cable”. http://www.thomann.de/gb/cordial_cfu_6_pc.htm
Are you sure you’re embarking on the right hobby?