Chi-squared test can be used to check the hypothesis, that given sample is from the given theoretical distribution. If the distribution is continuous then we should properly choose bins.
Question 1 : What are the suggestions to choose bins ?
SubQuestion 1.1 : If we are testing normal distribution or something similar, is there some particular suggestion?
SubQuestion 1.2 : If we are testing "bell-shaped", heavy tailed is there some particular suggestion?
Question 2: Is it corrected that we should choose such bins that $E_i$ (expected frequecies) are greater than 5, (if less, Yates correction should be introduced).
There is similar question, but with the focus on Poisson distribution (it is unanswered): How Do You Choose The Number of Bins To Use For A Chi-Squared GOF Test?