However, you can try these options:
1. Transliteration:
* अर्णव (Arṇava): This is the closest transliteration of "Arnav" using Marathi script. It uses the "ṇ" sound which is similar to "n" but with a slight nasalization.
2. Alternative Names:
* अर्जुन (Arjun): This is a popular Marathi name with a similar sound and meaning to "Arnav" (meaning "white," "light").
* अर्चना (Archana): This name is also popular and has a similar meaning (meaning "worship," "devotion").
Ultimately, the best way to write "Arnav" in Marathi will depend on your specific needs and preferences.