Druids have access to focus points, which are spent to cast order spells. A druid starts off with a single focus point and a maximum focus pool size of 1. Druids can improve the size of this pool with the Wind Caller, Invoke Disaster and Impaling Briars feats, but they require the druid be of the storm or leaf orders. Is there any way for a druid to get a larger focus pool without being in either of those orders?
Take a multiclass dedication, and choose multiclass feats that grant additional focus points. Focus points from all feats add together into a combined pool, of up to 3 points maximum, even if they're from different classes.
P. 302 "Focus Points from Multiple Sources":
It's possible, especially through archetypes, to gain focus spells and focus points from more than one source. If this happens, you have just one focus pool, adding all the focus points together to determine the total size of your pool.
Focus points are not differentiated by source; you can spend any of your Focus Points on any of your focus spells.