Regarding gst liability

If a registered person purchase goods or services from unregistered supplier, its responsibility of the registered person to pay the tax under reverse charge mechanism by raising self invoice.

1) No need to take registration as your limit is below 20 lakhs but please make sure than you dont have any other income from any sources.

2) You are unregistered supplier so supplies made by you are liable to te taxed under reverse charge (In the hands of service receipient {IF REGISTERED} ) - section 9(4) of CGST Act,2017 

Dear Sir,

First of all thanks a lot for suggestions,but further i am  having queries which is mentioned below.

1 Shall i have to take registration, when i m having other income from any other sources apart from Bussiness and proffesion Income??

2. If the service receiver is registered, than only he would be liable for GST under RCM when provided by unregistered supplier .??

3. Who will be liable for GST when both service provider and Service Receiver both are unregistered??

4. what period will be considered for the 20 lakh limit purpose , and which income is considered and which income is not considered for calculating 20 lakh limit??

5. Who will be liable for GST in following situations, when a Unregistred supplier for providing output serivce purchase inputs from -

                           a-- Unregistered seller

            or            b- registered seller