I am diagnosed with bells palsy and wanna ask that can i eat spicy things during this period and secondly can i join gym which i left due to bells pal?

Yes and yes: With a diagnosis of Bell's palsy there are no food restrictions. There should be no reason that you cannot join a gym and exercise if you want to do that.

Spicy foods OK: Bell's palsy is a weakness of the facial muscles usually on one side. Spicy foods are OK to eat. With regard to the gym acitivity, there will be a tendecy to drool on the affected side with exercise so have a towel handy.