Craft v3 gives 500 error on installation... how to get v2 instead
I definitely would not recommend trying to install v2. Craft CMS 3 has many improvements over v2, a strong plugin ecosystem, and it will be supported for significantly longer.

As for your setup issues, this is very likely some kind of a server config issue or Craft config issue. To find out which, we need to look at the error logs.

First, look to see if there are error logs in storage/logs/ (relative to your project root).

If not, then the request isn't even hitting Craft, so it's likely an Apache misconfiguration (usually the server root isn't pointing to the right place or such), and you can get more information by looking at your Apache logs.

If you do see logs there, then open up the web.log and search on [error] to see what the source of the error is. Often it is missing or incorrect database credentials.

c.f.:


Official Craft CMS Tutorial
Zen and the Art of Craft CMS Log File Reading
Setting up a New Craft CMS 3 Project