This word has several uses.

Go is used in a number of common expressions that refer to changes for the worse.

Common expressions are:

Go mad / go crazy / go deaf / go blind / go grey / go bald / go lame / go wrong / go bad / go off / go sour / go stale / go flat

He has gone mad.

The soup has gone bad.

The horse went lame.

The milk has gone sour.

What went wrong with it?

If a machine goes it works.

Is your clock going? (= Is your clock working?)

Go has several meanings. The meaning of go often depends on what kind of word comes after it.

These books go on the top shelf. (= These books are usually kept on the top shelf.)

The masts went in the storm. (= The masts broke in the storm.)

To go about something is to set to work at it.

Are we going about it in the right way?

Go by = be guided by

It is a good rule to go by.

Go down = sink

The ship went down without a trace.

Go for = be sold for

All his work went for nothing.

Go in for = take up as a hobby, pursuit

He went in for golf on retirement.