There are many causes of hair loss in females.
1. Due to stress/ covid/ illness/ surgery prior to hairloss.
2. Due to deficiencies of iron/
thyroid abnormalities/ vit d and
b12 deficiencies.
3. Female pattern baldness which occurs on the front of scalp in partition area.
So we first need to assess the cause, take history, see pictures, and then only I can guide you better.
Regarding hair oil, it does not help in hair regrowth, so you can completely avoid.