2 questions: Power Steering & Trans

This looks like a rupper cap seated where a dipstick should go.

 

I think your "I have a manual" comment was misinterpreted. This is the tube for an automatic trans. It plugs into the tube under the engine and bolts onto the side of the cylinder head.
https://www.toyotapartsdeal.com/oem/toyota~tube~sub~assy~transmission~oil~filler~35013-35250.html

 

https://www.ebay.com/itm/205120645914
3510635090 - Toyota Transmission Oil Pan. 3.4 LITER, 2WD. 3.4 | Toyota Parts Overstock, Lakeland FL

 

Can confirm - I did interpret that as "manual transmission", which is why I followed that up with a direct question.

 

Looks like it was plugged.

 

After looking at the photo again, and the photo of a pan with the attached part which is what you have, then basically you're missing the part of the tube that connects there, and the dipstick itself. I'd just try an online Toyota dealer and see if they're still available or you might find an after market one. Good luck and Let us know what you do.