I am planning to move from Pakistan to US for a Flex MBA, work, and settling with my partner within the next year. They're still open for the Spring Intake, but it depends on the time it takes for visa processing and other formalities. I'm an Entrepreneur and alongside my MBA I want to work on my venture. I'm looking for an answer to the following:
1. What kind of work is immediately available for entrepreneurs going through their part time MBAs? What's the average time it takes to land your first job in Boston?
2. How much do on-campus jobs pay?
3. Is 6 months a good enough timeline to estimate moving my partner to the US?

Google is your friend.

1. Entrepreneurs works for themselves. If you are looking for employment, you will almost certainly not be employed as an entrepreneur but in typical student jobs.

2. Other things being equal, you might expect the minimum wage (Massachusetts minimum wage of $14.25 per hour), since that is the median salary for both on-campus and off-campus jobs. Most international student can work only on-campus because of visa restrictions. 

3. I am not sure which visa class you would use for your spouse.  K-3 visa processing, on average, takes about 19 months.