there are many similarities among religions and denominations. people focus on the differences and start religious wars and terrorism and they shun the similarities. so I want to mention some similarities. christianity and islam both have fasting. catholics and orthodox venerate common saints. christianity and hinduism have a trinity concept. all religions as far as I know have a soul/spirit concept. and the list continues.
Actually, although I already replied, no. There are no similarities in each individual religion.
If each individual religion represented the letters U N I T Y.
They are not the same because they spell the word unity
They are not the same because they are letters
What defines this word is not the full word
What defines this word is not the nature of the word (that they are letters)
What defines this word is the individual shapes that make each letter what it is in itself. A U is not an N and a N is not an I and so forth.
So they are distinct. There is no similarity between these letters. The nature or foundation of the letter (the shape) makes them different. The word Unity and they are all letters does not make each letter the same.
That is why there are no similarities between religions.
The traditions are the shape of the letter which also is the core
The results of how the letter is used is similar to others when put together
They are all referred to as religions.
But because the core of these religions/their traditions and beliefs are not the same, they do not share similarities.