This is what we have been told in Germany:
The general advice is to try and contact your GP by phone, if you suspect you may have Coronavirus
Only people who’ve been recommended by a doctor to receive a coronavirus test would be tested - at a specially designated hospital testing point
Further outpatient coronavirus testing spots in hospitals will likely follow.
For patients who are not mobile or able to get to to a testing point, there are procedures in place for health professionals to visit homes for testing.
If you've spoken face-to-face with an infected person for at least 15 minutes, sat in the same row of the cinema or the same row of seats on a plane, or been coughed on or sneezed on by an infected person,
you're advised to self-quarantine
https://www.br.de/nachrichten/wissen/faq-coronavirus-die-wichtigsten-fragen-und-antworten,Rorgu8D
During this time, you should continue to be paid.
Those affected must stay at home and avoid contact with other members of the household as much as possible.
They must take their temperature twice a day and keep a diary of possible symptoms and contact with anyone.
As far as shopping and walking the dog is concerned: those who are in quarantine must ask friends, family or acquaintances to do so.
Friends would then have to leave the shopping outside the door of the quarantined person. < self-isolated >
What are the penalties for breaking an officially mandated quarantine?
Violation of the quarantine can reportedly result in severe penalties – namely a prison sentence of up to two years or a fine.
The health authorities check the quarantine by calling the affected person's home to talk to the patient and check how they are doing.
If no one can be reached, the public health department goes to the person's home and if no one is there, the police are called as a last resort.