There are many expressions commonly used in English to express similarity.
There is no magic rule to help you remember them. You just have to learn them. Sorry!
Take a look at the examples below.
To be like a kid in a candy store. (This is usually heard in American English.)
This is used to describe someone who is so excited by the location they find themselves in that they start behaving in a silly or childish way. Their behaviour is not as restricted as it normally would be.
E.g. He’s a massive car racing fan. When he won tickets to go behind the scenes of a race and meet some of the drivers he was like a kid in a candy store. He was so excited all day.
Like a shot.
If something happens like it shot, it happens very quickly or rapidly. It is done willingly with no hesitation.
E.g. If I got offered a job abroad, I’d be off like a shot.
Have fun learning English!
Louise