I would start with google analytics.
If you configure it correctly you can get quite far down the line for free.

Once you start seeing revenue and need more detail you can move over to one of the more premium or paid for systems.

Like many posted questions I would need more detail to be able to give you meaningful advice. My experience in this area is that I co-founded a web analytics consulting practice that was acquired by WPP in 2006 and have been working in customer acquisition since 2002.

What is your product or service? What are you key goals for setting up a dashboard? Have you done the most important work - carefully selecting 5-10 metrics that are both actionable and drive your business?

It all depends on how much data your business wants to aggregate under the same dashboard, and how many data sources you guys want to connect/consolidate. Solutions range from a simple Google Analytics deployment (either free or premium), to more robust suites like Tableau and Spotfire.

Also, you may use the APIs from every data source, and connect them via your own in-house resources.

Data Studio from Google is free, scalable up to as many dashboards as you can design, simple to use, and gives you the ability to gang data together from multiple sources all at once. Google Analytics, and Data Studio work great together. Since GA is free, it provides a great basis. If you are developing an App (mobile), then Firebase also is free, from Google, does a different yet slightly more app-mobile fovused analytics experience, and also is importable into Data Studio as a data source. Data Studio also queries BigQuery directly . Let me know if you need more info or have questions.
Best,
Chris