Obtaining leave (or citizenship in the UK by deception is a criminal offence which can carry a custodial sentence. If you are given over 12 months in the UK then UK Borders Act, the Home Office can serve you a deportation order under the automatic deportation provisions. If a deportation order is granted, you will be given the opportunity to appeal this but you only have 10 working days from the date the order is served to lodge your appeal. It is likely that you would then get a hearing within a couple of months.
There is no guarantee that the Home Office would seek to prosecute you, there is no consistency in their decision making - sometimes they choose to prosecute and sometimes they don't. You won't know until they actually make the decision and be aware of the fact that there is no limitation period on when they can serve you with a deportation order (ie, they can do it years after the event if they choose though your human rights arguments against this would be stronger the longer they leave it.)
If you are deported, in order to re-enter the UK you will have to apply to the Home Office to have your deportation order revoked setting out your reasons. If this is refused, this will also carry a right of appeal though you will have to remain outside the UK while your appeal is pending. You will not be able to re-enter the UK until the order is revoked.
If you have children in the UK, particularly if they are British then you have a good human rights argument under Article 8 ECHR as to why you should not be deported.
Deportation appeals are extremely difficult to win so if they have given you the opportunity to make representations and argue your case before they decide to deport you, make the most of it. I would advise you visit a solicitor who specialises in immigration as soon as possible and they will be able to advise you fully. Depending on your income, you may be able to get legal aid.