Q.Strawberries and tomatoes
Will it hurt my strawberry plants if I cut off the runners? I don’t want them to spread.
What would cause my tomato leaves to suddenly start curling up and the plant to start dying? Is there anything I can do to prevent this?

It won't hurt your strawberry plants one bit to trim off the runners, and this article will explain how: https://www.gardeningknowhow.com/edible/fruits/strawberry/growing-strawberry-runners.htm
Your tomato plants are suffering from either a virus or a challenging environmental situation (extremely high temperatures, no regular watering schedule, etc.). This article may help you: https://www.gardeningknowhow.com/edible/vegetables/tomato/tomato-leaves-curling.htm