You can order free rapid lateral flow tests to test employees twice a week in the workplace, provided your business is registered in the UK, you have 50 or more employees and your employees are unable to work from home. You must register on or before 31 March 2021 here: https://www.gov.uk/get-workplace-coronavirus-tests
If your business has fewer than 50 employees, local authorities are providing rapid lateral flow testing in the community through local test sites. Companies with fewer than 50 employees can direct workers to these test sites if they can't offer testing in the workplace. You can find a site local to your business here: https://www.gov.uk/find-covid-19-lateral-flow-test-site
Should you require any further support and advice on these matters then do not hesitate to get in touch.