Short answer:

• Eat only after sunrise.
• The usual Jain rule is Navkarsi: 48 minutes after your local sunrise, after doing morning shuddhi (bath), stavan/paath, and samayik/pratikraman.

Details to keep it proper during Paryushan:

• Shwetambar tradition: If you are breaking a Paryushan fast (e.g., after Attham/Atthai or the Samvatsari day), do Parana the next morning within the Parana time announced by your local Sangh/Panchang. This window starts after sunrise and generally closes within a set period; follow the published timing.
• Digambar tradition (Das Lakshan): Parana is done on Kshamavani day morning within the prescribed Paran Kaal from the Panchang for your city.

Practical steps:

• Check your city’s sunrise for that date; add 48 minutes (Navkarsi). Do morning rituals first, then take a little boiled warm water, and only then simple, saatvik food. Continue usual Paryushan disciplines (no roots, care in vihaar and ahar, no food after sunset).

If your Sangh has issued a specific Parana window for that day, follow that exactly even if it differs slightly from the simple Navkarsi rule.