Support and information for businesses can be found on the UK government’s main platform for providing information to business trading internationally – www.great.gov.uk.
If you have more specific questions, related to specific business sectors, have a look here.
If you have any enquiries, you can submit it through the DIT EU Exit Enquiry Service at this link.
Both British and EU companies can submit their enquiries.
You can access relevant information at EU’s trade help desk. DIT’s Digital team is currently developing a replacement for it, to ensure that international businesses are able to understand regulatory information including the tariffs, quotas and rules of origin which apply in a No Deal scenario.