You are looking at a ban of 12-16 months. The upper level for that range is 59, so with the accident as well, you could get 16 months.
There are 2 ways of reducing that.
One is mitigation - which can include remorse, no previous convictions and character references (2 or 3, in writing, which could include employer, to submit to the court) You can do this yourself. If you use a solicitor then you could expect to pay at least £300. There may be the option of the duty solicitor free at court but if it is a busy day they their focus will be on the more serious cases and they will decline to deal with you as there is no risk of custody in your case.
The other is to be offered, and accept, to do a Drink Drive Rehabilitation Course. This has to be offered in court during your hearing. It cannot be offered after that. This will get you a minimum of 3 months off your ban at 12 months, and up to 25% of a ban above that. It takes place over 3 days and you have to pay for it - costs £150-250 depending on the provider that you chose. The magistrates will probably offer you the course, but make a note to ask them if they do not.
You can of course do both, submit mitigation to try to keep the length of the ban down, then benefit from the reduction offered by the course.
Telling your employer depends on what your contract of employment says, and if you need to drive for work. They may take a dim view if you do not tell them, then your name and occupation appears in the newspaper the following week.....