Your brother is in BTec, so he must be about 22 years old. At this age boys are too much sensitive towards sex. They will try to do it with anybody at any cost. You are nearest to him so he will definitely strike at you and its also cool for boys at this age to loose their verginity.
But you are mature enough to avoid this. If he will succeed in seducing you and establishing a sexual relation with you then the bridge of ethical and moral values will be broken and then it may be possible that he will try for other female person in your house like mom, aunt etc..
You are also sexually aroused since last 15 days because now you are married and you know how it feel amazing to get a cock inside you but now you cant do it as your husband is out of country, so you are thinking now what should i do? I have nearest offer of sex with my bro, should I go for sex or should i wait? ethically and morally, it is wrong.
You should not do it as it will be incest and in near future it will affect both your lives very badly. So what should you do to avoid this situation? You can use dildo. You can have video sex with your husband at IMO OR WHATSAPP VIDEO CHAT. You can talk with your husband and tell him to visit at least once in a month for sex. Talk to him openly, besides Dubai is only 4 hours journey from India.
He can manage that, money should not be the problem as well as leave. In Dubai there is Friday and Saturday off. He can visit you and again resume his work without taking any leave but he should be hard worker only then he can travel that much else he will find an excuse. This way your desire will be fullfilled as well as your brother will be discouraged from doing such things.
If none of these work, and you anyhow want to make sexual relation with your brother then keep in mind few things. He should be 100% trustworthy, anything done between both of you should not be leaked at any cost. No camera or video should be used. No messages, sexual talk on phone. Condom must be used. You should not get pregnent at any cost.
However eventually you will get caught, but sometimes the person is clever enough to dodge all things and he or she will enjoy his life and will never be caught.
But you have to be Sherlock Holmes.