Update fellows_onboarding.md (#2184)

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Author: rct225

pages/docs/fellows_onboarding.md

@@ -5,28 +5,46 @@ title: Information for onboarding new IRIS-HEP fellows
 pagetype: doc
 ---
 
-## IRIS-HEP Fellows onboarding
+# IRIS-HEP Fellows onboarding
 
 Welcome to IRIS-HEP!  Congratulations on your acceptance into the IRIS-HEP Fellows Program.  We look forward to your contribution and collaboration.
 
 There are some additional items needed to complete the onboarding process.
 
-#### Payment Information <i class="fas fa-file"></i>
+### Payment Information <i class="fas fa-file"></i>
 
 You need to fill out a Payee Management Form in order to receive payment.
 
-*   For US Domestic students - <https://finance.princeton.edu/forms/supplierpayee-management>
-*   For International students - <https://finance.princeton.edu/forms/foreign-individual-payeesubstitute-w-8ben>
+#### US Domestic students
+If you are a US national completing the fellowship within the US, please fill out and return this form <https://finance.princeton.edu/forms/supplierpayee-management>
+
+####  Iternational students
+
+All foreign nationals, please fill out and return this form <https://finance.princeton.edu/forms/foreign-individual-payeesubstitute-w-8ben>
+
+For foreign nationals completing the fellowship within the United States, please send copies of the additional documents below (Please note the differences depending on your particular visa):
+
+##### Additional Required Documents
+
+|      |F-1 Visa                                                    |J-1 Visa                                                    |
+|------|------------------------------------------------------------|------------------------------------------------------------|
+|1.    |passport with picture, signature and most recent entry stamp|passport with picture, signature and most recent entry stamp|
+|2.    |Visa                                                        |Visa                                                        |
+|3.    |I-20 form                                                   |DS-2019 form                                                |
+|4.    |I-94 form                                                   |I-94 form                                                   |
+|5.    |[Substantial Presence Test form](https://finance.princeton.edu/forms/substantial-presence-test) |[Substantial Presence Test form](https://finance.princeton.edu/forms/substantial-presence-test) |
+
+### Tax Questions
 
 For tax purposes, we need you to answer the following questions:
 1.      Are you a US citizen/permanent resident or a foreign national?
 2.     Will you be physically located in the United States or your home country for the duration of the fellowship?
 
-Please complete and attach the appropriate form and answer the two questions above in an email message to <fellows@iris-hep.org>.
+Please complete and attach the appropriate forms with copies of any additional documents as needed and answer the two questions above in an email message to <fellows@iris-hep.org>.
 
 If you have general tax-related questions, please email <finance@princeton.edu>.  For personal tax-related questions, we encourage you to seek the advice of a tax professional.
 
-#### IRIS-HEP Web Site <i class="fas fa-link"></i>
+### IRIS-HEP Web Site <i class="fas fa-link"></i>
 
 Additionally, we also would like to add you to our Fellows webpage:
 
@@ -40,7 +58,7 @@ Once your pull request is merged and your fellows page is available on the webpa
 
   <https://github.com/research-software-collaborations/project_database/blob/main/README.md#changing-the-status-of-your-project>
 
-#### IRIS-HEP Fellows Slack Channel <i class="fab fa-slack"></i>
+### IRIS-HEP Fellows Slack Channel <i class="fab fa-slack"></i>
 
 Please also join the IRIS-HEP Fellows Slack Channel to interact with other Fellows and Mentors.