Male and female teachers don’t get jobs easily in Dubai, Sharjah or you can say in complete United Arab Emirates (UAE). Almost 98% of the teachers from South Asia are hired in schools here if they are living on their husbands sponsor visa. Also teachers with no UAE experience starts there career at 2.5k AED per month which is too low to survive.
For office assistant: 2 things are a must. Woman should be presentable and open to interact with opposite gender with no hesitation. And second is her grip on English or Arabic language.
Woman can move to UAE alone and this is not correct information that she must have mahram. She can move there alone, no mehram iqama required. On the other hand, job market is not that good at the moment. Woman will be investing a lot in visit visa, tickets and accommodation there and might end up with no job currently.