I got the clarification finally. Thanks for the support whatever you have given.
As conveyed above here was the problem,
Server A wants to access WSDL from Server B, and We are created a "Certificate request File" (P10b) file and shared with Server B, Now they have provided us with (P7b) file. Here was my doubt as to how to proceed.
Explanation :
P10b : "Certificate request" created by Server A in this case. This is a certificate request which means "This is my domain and I wanted to open a request for secured access" . Now this is what we share with Server B (Where wsdl is being implemented). Now since we want to access something from Server B over secured layer, Server B has to sign this request (signing here means approving any request which comes from Server A since this request holds the server name from where it is originating), Now this signing will be done by Server B which is when the certificate will be transformed from p10b to p7b which is what Server B will do and it will send this information to Server A.
Now at Server A we have this certificate called p7b, Server A will now have to convert this P7b to p12b which is the final version of the certificate. This conversion is a kind of decrypting technique which will be done by only the private key of Server A (which means only Server A can decrypt this) Once Server A converts this p7b to p12b which is the final version of certificate, now the server A can have access to the secured resources of Server B by using this certificate. If Server A want's to access WSDL from browser then the browser should have this certificate imported which can be done from the settings on the browser. If the wsdl has to be accessed from a soap UI then this can be done by SSL settings on SOAP UI.
I hope I have made clear. Please let me know if it's not clear anywhere.