In the context of:
A: 你要喝什么饮料?
B: 随便,都可以吧
Anything also can / Whatever is fine
In the context of:
A: 你要吃西餐或着日本餐?
B: 随便,都可以吧
Whichever is fine / Either is ok.
In the context of:
A: 你要怎么做呢?
B: 随便,都可以吧
Anyhow also can.
(For both meanings of anyhow:
1) In Whatever manner
2) Do carelessly, without a proper plan