How do you test conditions for two sample independent t test? If possible, please provide an example with excel outputs and explantions

Before Weight	After Weight
71.63	136.59
73.06	154.30
103.20	117.76
105.20	165.61
115.39	206.44
120.68	143.77
123.09	120.66
123.42	190.78
126.03	148.42
127.70	178.54
128.41	180.38
130.90	123.20
137.41	208.30
139.48	141.44
140.72	176.17
141.12	158.39
141.14	232.18
141.77	166.08
144.13	157.28
146.82	234.65
147.67	131.64
149.94	133.86
151.11	180.82
151.23	153.44
152.29	190.96
154.93	199.96
158.53	201.08
159.52	122.21
162.03	210.77
162.93	221.32
169.41	151.59
175.33	194.86
175.54	210.96
177.02	184.02
180.28	190.29
184.58	188.87
185.51	169.29
185.57	210.91
186.25	160.57
188.03	141.25
189.17	141.97
189.45	172.99
190.23	162.16
192.09	202.68
195.66	149.87
195.90	177.38
197.03	172.47
200.76	108.00
202.77	219.42
202.89	190.78
204.37	162.31
206.14	145.40
207.03	209.81
207.59	211.37
207.74	144.36
207.94	172.53
211.34	166.27
213.61	163.01
216.90	168.54
219.37	180.14
226.33	114.56
229.00	138.20
232.82	173.77
234.91	164.41
249.76	137.17
250.29	132.01