Your title question of if you can refuse to eat medicines -
whether a person can or cannot refuse to take meds depends on a lot of things.

here in the USA most do have the right to refuse medications but there are situations where that right is taken away.

for example ...

if the person off medication poses a threat of danger or harm to their self and others the following may apply..

court mandates / court orders
Conservatorship / guardianship
inpatient hospitalization

All these situations limit a person's rights to making their own mental and physical health decisions.

many other countries outside the USA have mental health systems, where a person does have right to refuse medications. I see your location is Bangalore (India), you may want to check on the mental health rules where you are located.

There are some cultures and religions that remove a persons rights to take or refuse medications.

my point only the person wanting to refuse medications can decide whether they have that right based on their own location, mental health system, religion, culture and so forth.

suggestion talk with your prescribing treatment provider, they will tell you what your mental health rights and responsibilities are based on your own situation, location and so forth.

If you have been court mandated / court ordered on medication you may need to petition the court for your rights back.

if you have a conservator or guardianship where someone else makes your mental and physical health decisions talk with that person, make you wishes and reasons why known so that they can better help you and better make decisions that fall in line with whats best for you and your health issues.