Definitely seek accommodations. The test goes by pretty quickly, so I think the average person wouldn't need a bathroom break if you go beforehand, but you might as well seek an accommodation to have peace of mind.
Yeah, they ask you to "pick a location" - just pick the one closest to you, and you'll eventually just get the flex survey confirming your needs for accommodation if any on LSAC/email maybe. Don't worry, your test center will be that bedroom desk haha
Not advice for focus, but you should look into applying for accommodations. You can get approval for extra time if you make a successful case that you need the extra time to write the test with the same difficulty as an "ordinary" writer.
Here u go: https://support.proctoru.com/hc/en-us/articles/360043127892-What-am-I-allowed-and-not-allowed-to-do-during-my-exam-
Talking aloud: Unless you have an accommodation, talking or whispering aloud during the exam is not permitted.
Hi there! Whether it be a prep test or a problem set, there is a drop down menu on the clock icon that allows you to select a time based on which accommodation you've received/want to practice with.