Goods return to supplier under GST

Mam, I am registered as a regular taxpayer. I want to return the goods purchased. Query- I will treat it as my normal sale & will issue a Tax Invoice in this regard & pay the output tax or adjust it with ITC . Query- Whether the process is correct ??

2) Output tax will not be collected from the company because they are our supplier. It will be adjusted from supplier’s balance in account. So, if we include Tax on sale in our output tax & pay it or adjust it with ITC. Then whether it is correct ?

3) Since goods are returned by us to the supplier , so whether i need to issue to Delivery challan also to the supplier besides Tax Invoice ??

4) Whether i need to give both Tax Invoice copy & Delivery challan copy to Transporter ??

Thanks..