no, they are different. A 跟 B 一起去 means A and B will go to some place or to do something. A 陪着 B or A 陪 B..... means B will go to some place or to do something, A just accompanies B, maybe because B dont want to go there alone or B needs help from A to do something for example, A跟B一起去买东西。 A and B go shopping together. A要陪B去买东西，因为B要买很多东西，他一个人拿不回来。 A will accompany B to go shopping, because B will buy lots of things, he cant bring them back alone. attention: 要+verb means be going to do something so 要陪 means be going to accompany so you should say 陪着 or 陪......

意思差不多。都是他们一起去。就是所谓的主动和被动。第一个句子是她被动。而下个句子是她主动跟随他去的。You understand?

她跟她男朋友一起去。She follows her boyfriend to go there 她要陪她的男朋友一起去。She goes there with her boyfriend