Yes, while a lot more cops carry firearms now than used to be the case, primarily because of terrorist attacks, they are all specially trained firearms officers.
If there's a situation where the police are called, or there's a planned operation, and firearms are thought to be involved, then a specialist team of firearms officers will attend, and they're trained to de-escalate whenever possible (though special rules apply when dealing with suspected suicide bombers).
So, for example, when there's a drugs raid and the police suspect there may be guns on the premises, the drugs squad and firearms officers will mount a joint operation involving two separate teams.
In a typical operation, first the firearms officers enter and secure the premises, (5 am is a popular start time for residential premises) and search and disarm the suspects, and then search then search the premises for weapons, while the drugs squad hold back and enter the building only after the firearms officers have completed their search (and made some arrests if they find any firearms that should not be there).