Dragonball Super: Do you think Broly has the strength to defeat Beerus?

Yes. Broly is easily God of Destruction tier, if not beyond it. During the Broly Saga, SSB Goku alone was stated in an interview to be nearing the level of the Gods of Destruction. This means SSB Goku is comparable to UIO3 Goku, who was also stated to be comparable to the Gods of Destruction. Broly's full power as the Legendary Super Saiyan is superior to Super Saiyan Gogeta, who was fifty times stronger than base Gogeta, who was stronger than Goku and Vegeta's full power combined then multiplied. Base Gogeta alone is significantly stronger than SSB Goku who was comparable to the GoDs, SSJ Gogeta is fifty times beyond that and LSSJ Broly is significantly superior to that. So yes, Broly could likely defeat Beerus.

Actually no, Beerus is more powful and intelligent,
I believe Beerus would defeat him in a fight,
It would be Extremely difficult, but Beerus becoming the victor.