Esa support group and 5hr course

Thank you
Id like to ask a further question ...
If I was to declare disability at the college and tick the form so that I am exempt from paying the fees is there a risk that the information could get passed on to DWP ?
This may be an area that cannot be answered here and if that is the case I understand ...

Also Gordon if I declare change of circumstances to DWP re ESA would they then notify PIP ? I know the assessments are separate but do these 2 bodies information share ?

my thinking at this point is to declare to DWP re ESA and PIP that I will be doing a 5 hr course and see what happens from there. its highly likely I will be re assessed and potentially put into the work related group. I am certainly not fit for full time work but want to do something towards my future and a 5 hr course seems a manageable first step. Of course I am not going to be able to live off the money and so would need to do some part time work to supplement my benefits. Can you please explain what work I can do within the work related group. I have read documents on it but im still not clear. Do the government allow to work up to 16hrs ? do they reduce the benefit if work is undertaken? What would be my best option working 2 days a week and college 1 day ? would the college count as work hours ? Would the GP write a sick note and say for me only to do part time hours ???
its all so unclear and I don't know how to look at my situation