Can you help to allow me to be able to download my 2016 tax transcripts

Sorry but right now you cannot get PLUS to access prior year returns.  The system is in transition from 2018 to 2019, and until sometime in December you will not be able to get PLUS.  You can get a free transcript from the IRS (or an exact copy of the return for a fee of $50):

You can get a free transcript from the IRS:   

https://www.irs.gov/individuals/get-transcript

I need to get a transcript 2016 downloaded to my email

Transcripts are gotten from the IRS...see link in above answer. 

can i get a transcript of my 2016 tax returns

You can get a free transcript from the IRS:   

https://www.irs.gov/individuals/get-transcript