In article ,
macon writes:

hello, I am planning to cut a larger opening in an outside wall made of
blocks. There is a large window at the moment and I want to install a
double french window.
I have permission from the building controls. I would like to know what
tools to use and how to proceed appart from supporting the load bearing
wall, which I know how to do. thank you.

If these are thermal blocks, a masonary hand saw goes through
them like a hot knife through butter, even if plastered (looks
like a regular timber saw, but with about 4 teeth/inch).
Actually, even a timber saw will work, but it will be wrecked
in the process and might not last for all your cuts.

--
Andrew Gabriel