How do I make my home town the first place that appears when I open the weather app?

Generally the first place that appears is your current location.

To make your home town appear first, do all the following:

• Settings > Privacy > Location Services > Weather = “off” (This means your current location weather will not be displayed)
• Make your home town first on your list as explained in the last bullet here: Check the weather in other locations on iPhone - Apple Support

See if this helps: Check the weather on iPhone - Apple Support