Blackhead is one of the grade of acne.
And yes dairy items and fat are considered as a culprits for acne. Acne is also a part of lifestyle disorder which can be stress induced, hormonal, environmental so first of all you need to correct these conditions
Next Steps
Consult me online for better understanding of your condition and for treatment part
Health Tips
Drink lot of water
Try yoga and meditation as lifestyle management
exercise regularly
DIY acne mask ( Consult me online for knowing about how you can take care of your skin during lockdown period)