You cannot specify a field inside the argument for Contains. We don't know anything about your object strucutre, so it's impossible to be precise, you would be looking for something closer to this:
data = data
.Where(p => p.fld_type.type.Contains("Login"))
.Where(p => p.fld_action.action.Contains("Login by Mobile Number"))
.Where(p => p.fld_status_code.statusCode.Contains("200"))
.Where(p => p.fld_output_value.opValue == "Success" || p.fld_output_value.opValue == "OTP has been sent"))
.ToList();
Of course, in order for this to return anything, ALL of those Where clauses would have to evaluate to True.