Hello,
yes you can do diploma in Psycology after 12th. It would be better if you do a bachelor's degree in psychology and complete master's and join job. Anyway you have to do UG and PG after diploma.
Here are some college names for suggestion look for one suitable for you.
for more college list please visit the link below:-
https://university.careers360.com/colleges/list-of-psychology-universities-in-india?degree=Diploma
hope it helps!
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