Input GST under transport of goods by road @ 5% tax

yes you can

yes but GST liable to pay under rcm and then self invoicing is done then only credit can availed

As per Notification No. 13/2017- Central Tax (Rate) dated 28.06.2017, Supply of Services by a Goods Transport Agency (GTA) in respect of transportation of goods by road to Specified Category Recipients are treated on Reverse Charge and the Recipient is Liable to pay GST.

IF GTA charge Forward Charge @ 12% availing ITC – Notification No. 20/2017 – Central Tax (Rate) dated 22ndAugust, 2017

So As to above If GTA charge 5% , recepient has to do RCM
&
If GTA charge 12 % , the recipient can take ITC

in my view if GTA charged 5 % then no need to pay as RCM.credit available to service receiver.

As per Notification No. 13/2017- Central Tax (Rate) dated 28.06.2017, Supply of Services by a Goods Transport Agency (GTA) in respect of transportation of goods by road to Specified Category Recipients are treated on Reverse Charge and the Recipient is Liable to pay GST.

So ask ur GTA to do not charge 5%, as his service is under RCM, (do not pay for the 5% charged by GTA or add it to freight cost)