Starting Monday, May 17, 2021, the British authorities will introduce a system of test rules and quarantine on arrival, differentiated according to the degree of spread of Covid-19 in the country of origin of the traveler. Thus, depending on the infection rate, countries will be placed on one of the 3 lists: 
Red, 
orange and 
green. The classification will be constantly re-evaluated.
According to the classification announced by the British government, Romania (like most EU countries) has been placed on Orange list (Amber), category for which the current rules are maintained. Thus, further after May 17, 2021, all persons traveling from Romania to England have the obligation:
to complete, no later than 48 hours before arrival, the Location Form (Passenger Locator Shape)to present a negative Covid Test Certificate (minors up to 11 years old are excluded). Negative PCR test (maximum 72 hours before travel) or negative antigen test is accepted. The test must be translated into English.to reserve and pay the cost of 2 more Covid tests to be performed during the quarantine period, days 2 and 8, of here.perform a 10-day quarantine period at a declared address prior to arrival.
More details about the rules for those arriving from a country on Orange list.
People are not exempted from the conditions presented above: • vaccinated, including the second dose; • who have had Covid in the last 3 months; traveling for a short period of 2-3 days.
We remind you that you can travel to the UK with your passport or ID card. Those traveling to work in the UK need a visa or residence (settled or pre-settled). For travel for tourist purposes, with a stay of less than 6 months, no visa is required (you do not have the right to work).
Hello,
From the above it is understood that people vaccinated with both doses must still be quarantined.
It was as if I were quoting “The exemption from the quarantine measure imposed applies to persons who have been vaccinated against the SARS-CoV-2 virus, including the second dose, and for whom at least 2 days have elapsed since the administration of the 10nd dose. ”
I no longer understand anything.
England does not apply exceptions for vaccinations. The information is for those traveling from Romania to England. And yes, the vaccine will not help you travel to England.
Only if you travel from England to Romania does the exception apply for those vaccinated. Pay attention to details! The measures are not reciprocal. Each country applies its own rules.