Yes
Some would include the SAT, ACT, and GRE.
Two tests are SAT and ACT.
The SAT's or the ACT's.
Both tests are college entrance tests, but it depends on the college. Some require only one, and some will take either.
If someone takes multiple ACT tests, then they Superscore them, meaning they take the best subsections on each of the tests and come up with a new composite. But keep in mind that MOST colleges and universities DO NOT superscore the ACT and only the SAT including all of the Ivy League and UC schools.
You can take both if you choose to do so. In the end, you can report the best score out of the two tests.
You can take practice tests from books like Kaplan and Princeton Review.
I highly recommend that you take either one one them within your junior year in high school.
To prepare for the ACT, some schools require freshmen/sophomores to take the PLAN and/or IACT. On your own, you can take practice tests by getting a copy of an ACt prep book, like Kaplan, Priceton Review, etc.
You study by doing practice tests and then go take another real test.
You can find many ACT prep courses online. Actonlineprep.com and actstudent.org both offer ACT prep plans, tests and details on where you can take the test which ready.
Recommended ACT practice tests are usually available through the ACT company themselves. These will be official practice tests that are more reliable than those from a private company.