From Bhagavad Gita 3.7-9:
But those karma yogis who control their knowledge senses with the mind,
O Arjuna, and engage the working senses in working without
attachment, are certainly superior. You should thus perform your
prescribed Vedic duties, since action is superior to inaction. By
ceasing activity, even your bodily maintenance will not be possible.
Work must be done as a yajña (sacrifice) to the Supreme Lord; otherwise, work causes bondage in this material world. Therefore, O
son of Kunti, perform your prescribed duties, without being attached
to the results, for the satisfaction of God.
The OP's interpretation of the Bhagavad Gita teachings is correct.
However, the following sounds more like the teachings of Jainism rather than Buddhism:
OP: Whereas Buddhism says, any act of Karma whether good or bad is bound to create attachment so the best way is to not indulge in any
karma altogether.
On the Devadaha Sutta (where the Buddha speaks to some followers of Mahavira, the founder of Jainism), the translator Ven. Thanissaro comments:
If the cause of present suffering were located exclusively in the
past, no one could do anything in the present moment to stop that
suffering; the most that could be done would be to endure the
suffering while not creating any new kamma leading to future
suffering. Although this was the Jain approach to practice, many
people at present believe that it is the Buddhist approach as well.
Meditation, according to this understanding, is the process of
purifying the mind of old kamma by training it to look on with
non-reactive equanimity as pain arises. The pain is the result of old
kamma, the equanimity adds no new kamma, and thus over time all old
kamma can be burned away.
In this sutta, however, the Buddha heaps ridicule on this idea.
First he notes that none of the Niganthas (Jains) have ever come to
the end of pain by trying to burn it away in this way ...
Thus the practice must focus on ways to understand and bring about
dispassion for the causes of stress and pain here and now. As the
Buddha points out in MN 106, equanimity plays an important role in
this practice, but it can also become an object for passion and
delight, which would then stand in the way of true release. Thus he
notes here that, in some cases, dispassion can arise simply from
on-looking equanimity directed at the causes of stress. In other
cases, it can come only through exertion: the mental effort — through
the fabrications of directed thought, evaluation, and perception — to
develop the discernment needed to see through and abandon any and all
passion.
The way to end suffering according to the Buddha is to end cravings through the Noble Eightfold Path. The way to end suffering is not through the avoiding of creating new karma.
The method stated in BG 3.7-9 is one of equanimity (performing duty without attachment to the results of actions), but it may not work according to the Aneñja-sappaya Sutta (MN 106):
When this was said, Ven. Ananda said to the Blessed One: "There is the
case, lord, where a monk, having practiced in this way — 'It should
not be, it should not occur to me; it will not be, it will not
occur to me. What is, what has come to be, that I abandon' —
obtains equanimity. Now, would this monk be totally unbound, or not?"
"A certain such monk might, Ananda, and another might not.'
"What is the cause, what is the reason, whereby one might and another
might not?"
"There is the case, Ananda, where a monk, having practiced in this way
— (thinking) 'It should not be, it should not occur to me; it will not
be, it will not occur to me. What is, what has come to be, that I
abandon' — obtains equanimity. He relishes that equanimity, welcomes
it, remains fastened to it. As he relishes that equanimity, welcomes
it, remains fastened to it, his consciousness is dependent on it, is
sustained by it (clings to it). With clinging/sustenance, Ananda, a
monk is not totally unbound."
"Being sustained, where is that monk sustained?"
"The dimension of neither perception nor non-perception."
"Then, indeed, being sustained, he is sustained by the supreme
sustenance."
"Being sustained, Ananda, he is sustained by the supreme sustenance;
for this — the dimension of neither perception nor non-perception — is
the supreme sustenance. There is [however] the case where a monk,
having practiced in this way — 'It should not be, it should not occur
to me; it will not be, it will not occur to me. What is, what has come
to be, that I abandon' — obtains equanimity. He does not relish that
equanimity, does not welcome it, does not remain fastened to it. As he
does not relish that equanimity, does not welcome it, does not remain
fastened to it, his consciousness is not dependent on it, is not
sustained by it (does not cling to it). Without clinging/sustenance,
Ananda, a monk is totally unbound."
Also, self-defense is not wrong according to the Buddha in the Mahaparinibbana Sutta:
"What have you heard, Ananda: do the Vajjis duly protect and guard the
arahats, so that those who have not come to the realm yet might do so,
and those who have already come might live there in peace?"
"I have heard, Lord, that they do."
"So long, Ananda, as this is the case, the growth of the Vajjis is to
be expected, not their decline."
However, despite self-defense, one should not carry unskillful thoughts like hatred and anger (from the Kakacupama Sutta):
"Phagguna, if anyone were to give you a blow with the hand, or hit you
with a clod of earth, or with a stick, or with a sword, even then you
should abandon those urges and thoughts which are worldly. There,
Phagguna, you should train yourself thus: 'Neither shall my mind be
affected by this, nor shall I give vent to evil words; but I shall
remain full of concern and pity, with a mind of love, and I shall not
give in to hatred.' This is how, Phagguna, you should train yourself.
Also, in Buddhism, there is no Supreme Creator God and there is no eternal absolute soul.