The correct name for this street is "San Felippo Road".
For example at https://www.cameroncad.org/property-detail/178418 you can see that both the property address and the mailing address for a house at this street is shown as "18131 San Felippo Rd Santa Rosa TX" by the appraisal district. (The map on the same website shows the incorrect name "Hooks & Hodges Road" because it uses the map from openstreetmap.)
Some of the street signs which are installed at this street use the correct spelling "San Felippo Road" while others use the spelling "San Filippo Road". The spelling "San Felippo Road" seems to be correct; that is the spelling which the appraisal district uses and if you enter the address at "18131 San Felippo Rd Santa Rosa TX" at https://tools.usps.com/zip-code-lookup.htm?byaddress they confirm that "Felippo" is the correct spelling used by the postal service. If you spell it as "Filippo" or "Felipo" in the input on that USPS website, they correct it to "Felippo".