User interface (Ubuntu) for my server on DigitalOcean

I wanna create a website in which I can be able to open Ubuntu on my DigitalOcean server, so it will be like if I open my laptop and be able to install softwares, transfer files or otherwise.

(briefly, I need to use my DigitalOcean server as if it is my laptop). The website will give me access to the screen similar to the attached one. Please, let me know before bidding how much that will cost and the required time.

Thanks