if you really need a vehicle that is reliable and fast, then I would say no, but as an extra car and a hobby to learn new things to restore, then yea. Either way you have it and good situation to learn new things with tutorials.
Here is a handy sheet of all the types and quantity of fluids and filters for the engine if/when you get to that:
if the engine is a 2.0
www.searchforparts.com/oil-change/toyota-2001-highlander-2.4l-2az-fe
if engine is a 3.0
https://www.searchforparts.com/oil-change/toyota-2001-highlander-3.0l-1mz-fe
You did not mention how many miles on the vehicle, that would also be a factor, if over 200k, I would move on. if less, use the synthetics in the links and you should be ok. Hope you found this useful.