a) Do some research
b) I'd suggest coming back with more specific questions having done your research
c) Asking about the batons and cuffs?... That's just weird. If you are looking to lock people up "for adventure" either join the Police proper or get involved in more S & M.
RMP TA? What do we do? We work in support of a Logistics Brigade, providing Provost Ops support as a Line Of Communications unit. The bread and butter stuff is installing and maintaining main supply routes. Controlling routes and ensuring the smooth running of convoys whilst responding to incidents on the route that could prevent much needed ammunition packets getting where it's needed.
We get quite a few numpties joining our unit becasue they think wearing the red beret gives them a power trip. If that's what you're looking you will be sorely disappointed. Whilst you will be taught basic policing skills (one or two weekends a year compared to the 2 yr progressive training a civvy plod gets). There are opportunities to work with the regs on policing duties. If you're identified as a walt, in it purely for the authority your given as a monkey then your existance will become a poor one.
Like the Seagull said, if batons and handcuffs floats your boat, then join the specials. If you like doing the army green stuff, but think the infantry endures too much hardship, we largely live out of our trailers and have such luxuries as stoves and cot beds depending on the situation.