Macros for modifing resources

My goal is to have a macro for my shortbow attack that decreases the number of my arrows by 1. There is any possibility to access the resources of a character_sheet?

Native macros cannot change values, only read/display them sorry. You would need access to the API to do this automatically (creator of the game would need to be a pro subscriber). An option would be to have an attribute on your sheet called 'Arrows' or 'Ammo' etc and link that to a bar on the character token, then you can easily reduce the number available from the VTT without having to open the character all the time?

There's also this stupid trick to set up a player dashboard that works at any level of subscription.