Currently Home Assistant has basic Bluetooth support for tracking Airtags and other trackers that are physically near the Home Assistant unit. Home Assistant also has support for logging in to an Apple account and querying information on the registered units, however tracking of your own Airtags is not supported.
There is software available, for example the python library Find my.py (GitHub - malmeloo/FindMy.py: π + π― + π = Everything you need to query Apple's FindMy network!), that implements tracking of Airtags after login in to an Apple account. Please implement support for this or a similar library so Airtags can be tracked.