Does my product need an Export Licence?
Does it perhaps fall under the "dual use" regulations?
Start here: https://www.gov.uk/guidance/beginners-guide-to-export-controls
Your next stop should be the Goods Checker tools via this page:
https://www.ecochecker.bis.gov.uk/ or
one of the related pages.
When you do need to apply for a licence, do it through SPIRE. Guidance page here:
https://www.gov.uk/guidance/spire-the-basics
and the actual system is here:
Would you like a local UKTI International Trade Adviser to contact you?
Use this export enquiry form or raise a ticket on this site.