ITC On goods purchased for personal use as well as business use.

yes Itc can be claimed on pro rata basis.

What is the exact use for the vessel in business?

Yes, ITC is available on Goods purchased for both business and personal purpose. But, For personal Use - 5% reversal is required to be done.

No goods used for the purpose of business alone allowed as input .....personal purpose input will be treated as end user....if tax officer finds it in Assessment then personal input claimed will be reversed with panalty also based on ineligible input claimed ..

Please refer GST Provisions w.r.t Common Credit. Proportionate ITC will be available for above mentioned case.

Agreed with all views.
This distinction between personal consumption and business consumption could very well become a litigious issue. The law provides that if any input is used partly for business and partly for non-business purposes, then credit would be available only to the extent it is attributable to business use.

ITC is availbale for  business purpose, cases where sevices or material procured for exlusively for personal purpose,ITC  is not available