Someone once asked...
Someone answered with kindness...
Communication, like many things improves with practice. If you can find low stakes situations where you can work on speaking more frequently, you can get better with less pressure. Holding mini-conversations with servers, bartenders, cab drivers, or other people you encounter briefly throughout the day can give you more experience without much risk if things don't go as well as you would like. It's also helpful to keep in mind that people tend to be more forgiving than you might imagine them to be, especially people who talk to strangers all day for their job!