To establish a relationship, you need to consider how you identify that relationship.
The normal "identifier" is called a KEY. A relationship in Access requires that one participant in the relationship have what is called a PRIME KEY (which we abbreviate as PK in this forum.) The other participant in the relationship has a FOREIGN KEY (FK).
A PK must uniquely identify one record in table. A table with a PK is a viable candidate for the "one" side of a one-to-many relationship. (Or a many-to-one relationship.)
Therefore, the first part of setting up any relationship is to decide which tables will be the "one" side and which will be the "many" side for each relationship.
Further hints to consider: A one-to-many relationship USUALLY (but certainly not always) implies a parent-child or overview-detail relationship. A many-to-one relationship USUALLY (but certainly not always) implies a lookup of something.
Your "type headers" appear to be many-to-one. Your transaction details will probably be more along the one-to-many line.
My advice to you is that while you are still a newbie and don't have to be broken of TOO many bad habits, IMMEDIATELY read up on "Database Normalization." Access Help is a good place to start, followed by a visit to Wikipedia.ORG for that same topic, and finally choose your favorite browser to search that topic. Please note that any decent web browser will come back with just short of a gazillion hits on that topic, so be selective in the web articles. Limit yourself to a few articles from the .EDU (educational) domain, usually offered by colleges and universities. Read more than one article because there are many ways to say what needs to be said. When it all starts to get familiar, you can stop reading.
When you build a database in Access, you want to shoot for 3rd normal form, which you will understand once you have read up on normalization. I'll stop here because until you understand normalization, some of the topics you need will be absolute gibberish to you.
