What type of work are you looking for? A good place to start might be to look at various roles within the industry; what ones you are specifically interested in and write down what skills you have to offer.
If for example, you are looking as a trainee driver or conductor role, you will have to consider unsocial hours and how you would get to the booking-on depot at say, 3 o'clock in the morning, or how you would get home after booking off at say, 2.30 in the morning. Do you have a bicycle or plan to take driving lessons in the near future?
You might be lucky to get a platform assistant job at your local station but might need to be flexible and travel to another station to cover sickness/leave etc.
Signalling jobs are being consolidated into large "super-centres" (ROCs) unless you live in an area where there are numerous signal boxes
May I suggest you be more specific in the kind of work you would like to do? This will also focus what options are open to you