Re: feet
I guess that is "cold feet to do something"
No, the phrase is never used in that way. It means to lose enthusiasm for something and the something must be understood for it to make sense. But the something is specified in the context, not in the phrase itself. For example:
The boys went out before dawn hoping to bag some ducks, but Bill got cold feet and they came home empty-handed for breakfast.
In that example the cold feet may have been literal rather than figurative, but you get the idea. Here is another one:
I fully intended to risk some money selling silver short, but I got cold feet after talking to a friend who had been badly burned speculating in futures.