Assuming that you are in the UK, most insurers won't have too much problem in providing you with cover, although you might find that the very cheapest providers will flinch a little and may try to impose a premium loading. You will need to disclose your intentions to train and may need to provide details of your supervised course so that an underwriter can ascertain that you aren't learning by jumping off a cliff with angelwings on your back!
On-line applications probably won't be able to cope with your requirement by the way as the underwriting system won't recognise the risk.
Hope this helps. (this is how I earn my pennies that pay for lessons!)