4-Node SSH

Hi, I am looking for a directions and a script (preferably bash and with a separate config file) that will allow me to ssh/scp and  get an xwindows terminal on a remote server from a workstation as shown in the diagram below. Workstation(A) -> Proxy1(B) -> Proxy2(C) -> Server(D) Some notes about the current configuration - The intermediate proxies (B and C) and server(D) have my public ssh key. - Workstation A has both public and private keys - B, C, and D are running RHEL 7 - Workstation A is running Centos 8 - I have *VERY* limited access to B and C - I have FULL root access to workstation A, and the ability to make changes there - There are various servers(D) that I will be connecting to. I would like to assume that I have limited access there as well. - Proxies B and C use the same username - Server D uses another username. - The solution must be secure such that other users on B and C can not use the same connections. - The boxes are very closely watched from a security standpoint. - I am currently authorized and able to hop from one host to the next by connecting to each, one at a time. The person providing the above directions/script will not have any access to the servers that I will be testing from. For this reason, it may take longer than expected to troubleshoot. In order to determine which bidders have actually read this proposal in full before submitting their proposal, please let me know what your favorite ice cream flavor is. Thanks