After getting surgery on my nose (for a deviated septum), will exercising be easier for me?

Yes. Depending on whether that was a problem with oxygenating your blood and depending on whether the surgery was done properly and you have two very clear open nasal airways and you breathe through your nose easily now. It is important to breathe through your nose as your immune system filters many "invaders" via immunoglobiulins canlled iga's. Keeps you healthy!