Question

I(go)to the Black Sea coast last summer.

Answer 1

went, т. к. нужна вторая форма просто, а это глагол неправильный

Answer 2

I went to the Black Sea coast last summer
went- прошедшее время go

Answer 3

It looks like you're describing a past event. The correct sentence would be: "I went to the Black Sea coast last summer."