Can you setup a Function inside a table in Base

In Access I have 2 Functions or Expressions (not 100% on the terminology) and I would like to know if the same can be done in Base.

They are:

  1. [Field1]+[Field2]+[Field3]+[Field4]+[Field5] to add them all into Field6
  2. IIf([Total]>=400,“Statement1”,IIf(([Total]>=300) And ([Total]<400),“Statement2”,IIf(([Total]>=250) And ([Total]<300),“Statement3”,“StatementDefault”))) to categories different values that will be used for quick searches

Thanks in advance for any help provided

Please any ideas where to start with this!!

Alan Forrester