Barsel i got the same letter a few days ago. Its a generic letter for people who are on the 'highly Vulnerable' list and not specifically aimed at you personally. They are only suggestions, and advise you to contact a health professional if you are concerned.
"You should consider advice from your health professional on whether additional precautions are right for you. However, as someone with a health condition, you may want to consider, alongside any advice from your clinician, if additional precautions are right for you. These could include:
considering whether you and those you are meeting have been vaccinated – you might want to wait until 14 days after everyone’s second dose of a COVID-19 vaccine before being in close contact with others
considering continuing to practice social distancing if that feels right for you and your friends
asking friends and family to take a rapid lateral flow antigen test before visiting you
asking home visitors to wear face coverings
avoiding crowded spaces "