The answer is yes to both questions.
However, the important thing to note about the timeout value is that you shouldn't necessarily expect perfect timing due to how the system checks for activity as noted in the description of
timeout value here
The last active session time value isn’t updated until halfway through
the timeout period. So if you have a 30-minute timeout, the system
checks for activity when 15 minutes have passed. If you update a
record after 20 minutes, your timeout resets because it’s 5 minutes
after the active session time is checked. In that scenario, you have
another 30 minutes before log out occurs, for a total of 50 minutes.
But if you update a record after 10 minutes, logout occurs 20 minutes
later (30 minutes total) because there was no activity in the past 15
The help doc concerning managing session policies also states the following for understanding which timeout policies will affect your connected app if you don't set one on the connected app itself:
You can control how long a user’s session lasts by setting the timeout
value for the connected app, user profile, or org’s session settings
(in that order). If you don’t set a value or you select None (the
default), Salesforce uses the timeout value in the user’s profile. If
the user’s profile doesn’t specify a timeout value, Salesforce uses
the timeout value in the org’s Session Settings.