To facilitate the coronation of Bharata and to ensure a reign of fourteen years, queen Kaikeyi asked the following boons from king Dasharatha:-
All arrangements have been made to undertake Rama's coronation. Let my Bharata instead be coronated on this occasion itself. Rama has to take refuge in the forest of Dandaka for fourteen years and let him become an ascetic wearing rags, deer skin and matted hair.
Sri Rama loved and worshipped Queen Kaikeyi like his own mother.Sri Rama went on exile to fulfill the boons asked by Queen Kaikeyi.
But, Sri Rama could not have lived exactly like an ascetic during his exile, due to his Swa-dharma.As explained in scriptures, Swa-dharma is our personal dharma, which is the dharma applicable to our context, situation, maturity, and profession in life. This swa-dharma can change as our context in life changes, and as we grow spiritually.
This rule is explained in Srimad Bhagavad Gita, Chapter-3, verse 35:-
श्रेयान्स्वधर्मो विगुण: परधर्मात्स्वनुष्ठितात् |
स्वधर्मे निधनं श्रेय: परधर्मो भयावह: || 35||
Translation
It is far better to perform one’s natural prescribed duty, though tinged with faults, than to perform another’s prescribed duty, though perfectly. In fact, it is preferable to die in the discharge of one’s duty, than to follow the path of another, which is fraught with danger.
Verse 47, Chapter 18 of the Srimad Bhagavad Gita, is also highlighting this rule, and is relevant in this context:-
श्रेयान्स्वधर्मो विगुण: परधर्मात्स्वनुष्ठितात् |
स्वभावनियतं कर्म कुर्वन्नाप्नोति किल्बिषम् || 47||
Translation
It is better to do one’s own dharma, even though imperfectly, than to do another’s dharma, even though perfectly. By doing one’s innate duties, a person does not incur sin.
Sri Rama's Swa-dharma was - to always destroy evil and protect righteousness(uphold Dharma).Advice given by Maharishi Vishwamitra to Sri Rama:-
Do your duty as a Kshatriya, the ruling class, and protect virtue and eradicate vice
The bow and arrow, were divine instruments for actualization of Swa-dharma.