I have changed a number of clutches and gearboxes, but the question you need to ask yourself is this. Have you got the appropriate and possibly special tools, an undercover working area, the time and most importantly, the knowledge to do the work? If you are a fairly competent DIY motorist, then you should be OK, but if not, then these are jobs to trust to
garage. You may well find that doing it yourself (if you get it wrong) could well be a very expensive mistake.
Golden rule of ALL car jobs.......if you don't know what you are doing, leave well alone. Hope this helps. Getting a Haynes manual is one thing......doing a job like this unless you are capable of doing it, could well turn out to be your big nightmare.
A Renault forum may be a good start, if you want to go ahead. Others who have done these jobs on your model may have useful advice.