Integrating neo4j with express through the neo4j driver

I am confused about integrating neo4j with cypher language with express node js . I found many tutorials online but i can't understand things like :
1- the difference between transaction and
2- how to import the session object to be used in different routes

Hi taghrid_mahdy,

welcome to the Neo4j community!

Concerning your first question: I think the Neo4j manual could help you here getting the difference between e.g. read transactions and Neo4j documentation - Neo4j Documentation