I'd say take your CBT and see how you feel before doing anything else. You'll be surprised at how vunerable you feel on a motorbike even if you're used to riding a bike on the road. If you do your CBT you'll get two years to ride around. If you're not planning to get anything bigger than 125cc its probably not worth if financially to get lessons and do the test. The bike test is however getting harder and harder and with it more expensive to do. I would advise getting a proper jacket, trousers, gloves and helmet. You can lose a lot of flesh before you stop skidding down an road on your backside if you're only wearing a pair of jeans. It doesn't have to cost a fortune to kit yourself out. Lidl's motorbike specials are excellent value for money.
Another vote for scooters from me. Middle aged men suddenly getting motorbikes smacks of deeply repressed sexual urges rearing up and getting repressed again. I've got a Gilera Runner for commuting (although its a 200cc you can get a 125cc for learner legal), you do get a little bit more weather protection and a bit of storage under the seat. For commuting its excellent as its a twist and go just dull as dishwater to ride.
Another vote for scooters from me. Middle aged men suddenly getting motorbikes smacks of deeply repressed sexual urges rearing up and getting repressed again. I've got a Gilera Runner for commuting (although its a 200cc you can get a 125cc for learner legal), you do get a little bit more weather protection and a bit of storage under the seat. For commuting its excellent as its a twist and go just dull as dishwater to ride.