Belatedly catching up, but, having seen
@some bloke's post, I think he has covered most of the pertinent points so I don't have a lot to add to it. If anything I add is wrong I hope it will be corrected by a criminal law practitioner.
The proceedings were evidently commenced by the laying of an information. The effect of this is that when you lodge your completed statutory declaration with the court, you are not required to provide a statement at the same time indicating whether you intend to plead guilty.
Provided the SD reaches the court in good time, the proceedings against you will be rolled back to the point at which the application for a summons was made. The conviction recorded against you in your absence will be treated as void, and the debt collection agency will, for the time being at least, have no lawful grounds for demanding from you payment of the fines, etc, the court then imposed. However, the application for a summons will remain valid and should in due course lead to the service upon you of a fresh summons giving you notice of when you have to attend court to answer the charge against you.
This should provide you with a breathing space within which to contact Northern Trains' prosecution department and try to negotiate a settlement that will avert the risk you face of being convicted of an offence. Don't delay in taking advantage of that opportunity.
I do not see it being to your advantage to respond here to the question about whether you gave a false address or DoB. You know whether or not you did so, and must be prepared to deal with the consequences if you did. I emphasize that you should take care to make a truthful statutory declaration, as you may face severe consequences if you do not. Having said that, I am inclined to agree with
@some bloke that an additional prosecution for giving false details about yourself does not seem particularly likely once you have made it clear to Northern that you are anxious to agree a resolution of your case that is acceptable to that company.
I don't propose to add anything now about the way in which you approach Northern in an effort to reach agreement with them save to say that the threads in this section of the forum contain some excellent guidance in that respect; in particular
@Hadders has offered some guidelines in a number of threads that you may find helpful.