You have found an advertised role you are interested in, so how best to go about contacting the company?
In response to a job ad: If you have seen a role that interests you, chances are the job ad specifies how the employer would like you to apply (either online or in writing or through a recruitment agency). Be careful to follow the instructions in the job ad, as this is your chance to demonstrate your attention to detail. Be mindful of key things like getting the spelling of the recruiter’s name and the name of the company correct.
Not in response to a job ad: If you have identified a company you would like to work for but are not sure if they are currently hiring, this is often called approaching the company speculatively