Tranlation decktop app UI to the web or azure

My decktop app doese some math with loaded txt data. UI is single page. It has 2-3 interactive charts. Iteractive invilves zooming and panning, editing color scale for contour mat and editindg input data by drugging the chart. The task is creating web UI based on existing decktop UI. I want to use it as HTML code on the WIX web site. User have to be able to load several txt files and save result. Math can take several minutes and loads the CPU. It can be done as: 1. web app witch usage of local CPU (if it possible) or 2. Azure app. Azure app have to be able to run on my free test Azure account becouse it is non profit project. Actually, if you have better ideas, I well glad to discuss.