Growing Bell Peppers....

I always do. When you get a rain that softens the ground coupled with a big wind, they'll topple. Especially when they have peppers on them.

Yes. Put a tablespoon of Epsom salt around the drip line for healthier and larger peppers.

We do not stake bell peppers that we grow commercially, the bush will support it weight. That said, in a garden with a couple of plants I probably would. If you have them together. put a stake on either side of them and "trellis" the string from one stake around it and back the the starting point. As the plant grows, add more string. This is the way the commercial guys do all their vegetables.