Jobs and money vary massively all over the country, I'd research whats on offer before paying out for the training.
There isn't as much work as a lot of training companies make out.
Most of the work these days will be agency work which can be up and down.

HGV driving is long hours and often shite with a lot of manual labour.
Expect 10 hour minimum days and a mx of 15 hour days.

I don't feel truck driving is a great career choice however its better than nothing.

Do your research and go from there