Secure Portal Development For Clients to upload Personal Info Held in secure server inside the EU.

I require a IT professional to develop a secure portal which will allow my individual clients to upload their personal information as I specify. The uploaded information will need to be stored in some kind of secure server within the EU. I require advice on this and pointers for the best one to go with i.e. Amazon etc. The person I appoint to this must have understanding of the legal legislations around data protection and should be familiar with GDPR compliance in order for this portal to accept personal information. The data I retain will be processed and stored in line with GDPR and existing Data Protection ACT. I will need the person to come up with a data sharing agreement between my organisation and the service user. If you are interested in project then please submit a proposal highlighting what you will offer me and your competency and qualifications appropriate to the outline above.