Ranger that gains spell slots on critical hits and gives out spell slots to other players

Level 3: Roots of Generations

As a bonus action, you can give one of your spell slots to replenish another character's expended spell slot at an equal level.

Level 3: Tree of Life

Also gain access to the Druid's spell list

Level 7: Sap of the Tree

At level 7, gain an expended spell slot of your choice when you critically hit with an attack roll.

Level 15: Boon of Life

You can now regain 2 expended spell slots of your choice on a critical hit with an attack roll

Level 11: Syphon Life

As an action, you can a creature you can see within 60ft of you with a beam of life energy. On a failed wisdom save, the creature takes 6d10 Poison damage, or half as much on a successful save, and up to 5 creatures of your choice in a 60ft radius (including yourself) heals for the amount of damage dealt. You can only do this once per long rest.