You can find further guidance here:
Brexit: new rules are here
UK distributors and suppliers:
You’ll need to confirm whether you or your supplier will act as an ‘importer’.
You’re an importer if you’re the first one bringing goods from outside the UK and placing them on the market in Great Britain.
If someone has already placed a good on the UK market before you sell it in Great Britain - or if the manufacturer has appointed another UK-based person to carry out importer duties - you will remain a distributor and will not have any additional responsibilities.
As an importer, you’ll need to make sure that:
• goods are labelled with your company’s details, including your company’s name and a contact address. Until 31 December 2022 you can provide these details on the accompanying documentation rather than on the good itself if you import certain goods from the EEA (and in some cases Switzerland).
After 31 December 2022, your details must be affixed to the product or, in circumstances where the legislation allows, on the packaging or an accompanying document
• the correct conformity assessment procedures have been carried out and that goods have the correct conformity markings
• the manufacturer has drawn up the correct technical documentation and complied with their labelling requirements
• you maintain a copy of the declaration of conformity for a period of 10 years
• goods conform with the relevant essential requirements
You must comply with the above for goods placed on the GB market regardless of whether they are CE or UKCA marked.