This Lenovo Chromebook 3 11, model number 82BA001FUS, ships with the Chrome Operating System installed and uses Google Workspace for office type programs. Google Workspace is completely compatible with Microsoft Office Programs and this is a free service through the Google Server. If you currently have a Microsoft Office 365 Account, you can access that existing account through a Chromebook. Here is a link to more information: https://support.microsoft.com/en-gb/office/how-to-access-microsoft-office-on-a-chromebook-32f14a23-2c1a-4579-b973-d4b1d78561ad#:~:text=Open%20the%20browser%20on%20your,with%20your%20Microsoft%20365%20subscription.

Yes. This Lenovo ThinkPad X12 Detachable 2 in 1, model number 20UW000SUS, ships with the detachable keyboard and Lenovo Precision Pen included.

No. This Lenovo IdeaPad Flex 5 16, model number 82RA000DUS, is compatible with an AES Protocol active/digital pen, which is sold separately, like this one: https://www.bestbuy.com/site/wacom-bamboo-ink-smart-stylus-for-windows-ink-2nd-generation-gray/6374981.p?skuId=6374981

That will depend on the requirements and compatibility of the specific APP you want to use. This Lenovo Chromebook 3 11, model number 82BA001FUS, ships with the Chrome Operating System installed and is compatible with Google play Store APPs. Not all APPs at the Google play Store are optimized for the Chrome OS. We recommend you check with the specific APPs software publisher's web site, of the specific version of the APP you want to use, for their compatibility with the Chrome operating system and the minimum/recommended hardware requirements (Is a Graphics card required, the processor speed and the minimum required system RAM and the minimum available hard drive space) to run their program, then compare those requirements to this Chromebook's configuration.