For Misdemeanor theft you're unlikely to get a jail sentence especially if the misdemeanor theft if your first offense.
The most that will likely happen is you get arrested, get bailed out, and either get probation or pay a fine but in some cases you could get a year in jail for misdemeanor theft.
When you steal something with a value of $1,000.00 or more then it becomes felony theft which could get you a prison sentence of 3 or more years in prison.