Forcibly termination within 3 months of job

Hi All, I have joined a company Morningstar in Mumbai as Application Architect on Dec, 2017. Before this, I was working with Tech Mahindra Mumbai. They(Morningstar) asked me to abscond from Tech Mahindra and join their company. When I said let me complete the Exit process of Tech Mahindra, they asked me to avoid it and join them immediately. They also sent Offer letter without having Terms and Conditions, Company Policy and all. When I raise a concern, they said I will get Appointment Letter having all that Policy details at the time you join here. Being a techy having less knowledge about Company laws I abscond from Tech Mahindra and joined here in Morning Star. Within 2 months of my service there they started raising concern that your performance is not upto the mark which is realistically not true since I have more than 14 years experience and worked with some reputed organization at the role of Technical Architect, Solution Architect, Technical Manager. Nowhere my performance was a concern and I spend ample amount of time with my previous organizations(more than 2 to 3 years for each). Now morningstar is started harassing me to for PIP or they will terminate my employment. I am really very much upset from this incident and my family and career is on toss due to such inhuman behavior of Morningstar. Kindly suggest what should I do to save my career and my family. Thanks a lot!!