In which lesson do we learn how to line up customer id's to relate to other table without entering the ID for each record in the other tables?

I basically have a table of "customers/clients" I want to create a few other tables of "clinic admits" and another of "client referrals" and I want them to all relate to the Custmer/Client ID in table one. I would like to import that data, but do I need to enter the Customer ID/Foreign ID for each record in each table or is there an easier way?

Tahnks..

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Reply from Alex Hedley:

Do you have any matching data in both the client table and the table you wish to join too?