OK, let's work through this together. We're starting with 921 and we're going to multiply it by 63, which means we add 921 to itself 63 times.
Step 1: 0 + 921 = 921
Step 2: 921 + 921 = 1842
Step 3: 1842 + 921 = 2763
Step 4: 2763 + 921 = 3684
Step 5: 3684 + 921 = 4605
Step 6: 4605 + 921 = 5526
Step 7: 5526 + 921 = 6447
Step 8: 6447 + 921 = 7368
Step 9: 7368 + 921 = 8289
Step 10: 8289 + 921 = 9210
Step 11: 9210 + 921 = 10131
Step 12: 10131 + 921 = 11052
Step 13: 11052 + 921 = 11973
Step 14: 11973 + 921 = 12894
Step 15: 12894 + 921 = 13815
Step 16: 13815 + 921 = 14736
Step 17: 14736 + 921 = 15657
Step 18: 15657 + 921 = 16578
Step 19: 16578 + 921 = 17499
Step 20: 17499 + 921 = 18420
Step 21: 18420 + 921 = 19341
Step 22: 19341 + 921 = 20262
Step 23: 20262 + 921 = 21183
Step 24: 21183 + 921 = 22104
Step 25: 22104 + 921 = 23025
Step 26: 23025 + 921 = 23946
Step 27: 23946 + 921 = 24867
Step 28: 24867 + 921 = 25788
Step 29: 25788 + 921 = 26709
Step 30: 26709 + 921 = 27630
Step 31: 27630 + 921 = 28551
Step 32: 28551 + 921 = 29472
Step 33: 29472 + 921 = 30393
Step 34: 30393 + 921 = 31314
Step 35: 31314 + 921 = 32235
Step 36: 32235 + 921 = 33156
Step 37: 33156 + 921 = 34077
Step 38: 34077 + 921 = 34998
Step 39: 34998 + 921 = 35919
Step 40: 35919 + 921 = 36840
Step 41: 36840 + 921 = 37761
Step 42: 37761 + 921 = 38682
Step 43: 38682 + 921 = 39603
Step 44: 39603 + 921 = 40524
Step 45: 40524 + 921 = 41445
Step 46: 41445 + 921 = 42366
Step 47: 42366 + 921 = 43287
Step 48: 43287 + 921 = 44208
Step 49: 44208 + 921 = 45129
Step 50: 45129 + 921 = 46050
Step 51: 46050 + 921 = 46971
Step 52: 46971 + 921 = 47892
Step 53: 47892 + 921 = 48813
Step 54: 48813 + 921 = 49734
Step 55: 49734 + 921 = 50655
Step 56: 50655 + 921 = 51576
Step 57: 51576 + 921 = 52497
Step 58: 52497 + 921 = 53418
Step 59: 53418 + 921 = 54339
Step 60: 54339 + 921 = 55260
Step 61: 55260 + 921 = 56181
Step 62: 56181 + 921 = 57102
Step 63: 57102 + 921 = 58023

So, 921*63 = 58023