Look to East Asia, and Australia (NSW aside) and New Zealand. Europe too. Eg. Germany, France, Italy.
Pandemic border control. UK borders have been and continue to be pretty much wide open for any and all new strains. And there's no such thing as 'home quarantine'. The whole point of quarantine is to stop the spread. That doesn't mean only after the potentially infected person has travelled, often on busy public transport, to their home or hotel.
Mandatory masks in indoor public spaces including schools, like most of Europe, USA, and East Asia (the minority of genuine exemptions excepted). Possibly at times of high infection, follow CDC advice to mask in busy public spaces outdoors too.
If lockdown, do it properly and enforce it. Like Europe, paperwork required if out and about for essential reasons. Curfews. Strict but short is best when it comes to lockdowns.
Ventilation. Fitted filtering systems in schools and on public transport.
Self isolation support.
Include all the main symptoms on the NHS list and offer tests for all main symptoms.
Educate public. On the symptoms, and on what airborne infection means, on infection control. Things we used to understand in the past - back when we had TB sanatariums and isolation hospitals.
Proper PPE for health and social care staff. FFP2 or FFP3 masks. In fact, do as Germany advises and FFP2 masks for the public too in crowded public spaces, i.e. public transport.
mRNA booster jab all clinically vulnerable and over 40s (risk increases at 40/45, not 50).
Provide access to treatment for Long Covid patients. Including specialist scans (routine scans don't always pick up the damage).
Regeneron treatment for patients who for medical reasons aren't protected fully by vaccines.
CEV list to include those at highest risk of hospitalisation and death (not necessarily the same as increased risk of infection).