Diesel cars battery drain issue, please help.

I bought Ecosport diesel in Jan 2021 and its been 4 years, my cars battery got drained thrice. My running is very low and as it was my first car, I didnt know that I should have gone for petrol varient. It is single hand driven and gets out once in 2-3 days only(hit 28k kms only). How do I tackle battery drain issue. Will battery change help or uts battery is in good condition?