A Covid vaccine is very important for everybody as it develops antibodies similar to antibodies in a recovered Corona patient. In the first week of May 2021, Sputnik has launched single - shot vaccine with 80% efficacy. Otherwise, in most of the vaccines, we require a course of 2-3 doses at different intervals to build a considerate immunity in our body. So generally, the first dose builds an amount of antibodies that are able to create 30-40% immunity in the body if the virus attacks after a week of the dose. It is after the second dose of the vaccine that is to be injected after a few weeks to build further antibodies and thus create an immunity of day 60-80%. With that kind of immunity built in the body you are well equipped to defeat Covid.
One thing is pretty sure that if I have taken two doses of vaccine well in time with prescribed timeframe and correct gap between the first and the second dose of vaccine, a Corona attack after that will not be that serious to cause any severe damage to my body. It will always be a mild attack that can be managed staying at home taking appropriate precautions and medications.