I am trying to auto enter dates based on a date in an initial date field.
Please make sure to post the question in the body of your post, as long titles can be confusing to read.
That said, your calculation is easy:
YourTable::InitialDateField + 30
would add 30 days to another date field.
watch this training video for instructions on how to setup an auto-enter calculation.
Auto-Enter Options for Fields | FileMaker 14 Training Videos - YouTube
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