Do I need a 30 min break or 45 mins if extending my driving time to 10 hours ?
Seriously? You don’t ever need to have extended your time to know the answer. I’m not going to give you the answer because I can’t believe your knowledge is lacking so much you don’t even know something so basic and I think that actually you’re just too flipping lazy to work it out so you can work for the answer.
What do the rules say about the maximum time you can drive without a break?
How long does is the minimum time that break needs to be?
What is 10 divided by the answer to 1)?
Therefore what is the answer to your question?
Second if I I take the mentioned break at four hours will the other 30 mins be carried over onto the extended time on the tacho ?
You’ve got a max of 10hrs driving, doesn’t matter how you take the breaks as long as you don’t exceed 1) above.