Itc on packing bags

Yes you can .
even though it's not charged separately on bill when it's supplied , but Assume that included in value of goods(sugar) being supplied.

Yes... You can avail ITC for the PP bags.

Yes you can avail ITC on Purchase of PP bags since it is used in the course of or furtherance of business. Section 16(1) of the CGST Act 2017 states that ITC can be claimed on all goods or services which are "used in the course of or furtherance of business" ( subject to Section 17(5) of the CGST Act 2017 i.e. BLOCKED CREDIT ).

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