If you ask whether you are able to run Adobe Flash (or any other non-free
software), the answer is "yes". It's your Freedom Zero, any free/libre
operating system should not stop you from running Adobe Flash, even if it's
broken beyond repair.
Gnash is only compatible with very old Flash versions, so don't bother to try
it. Here is a remainder: Flash will die in next year (Adobe will completely
stop supporting it), and an important fact is that FSF no longer marks Gnash
as a high-priority project.
Finally, please say "GNU/Linux" if you refer to the operating system, rather
than the kernel.
