I want to upgrade my operating system on 2 computers.

I have a Mac Book Pro 13" 2017, that I bought in 10/19/2018: Serial #FV***V29. Its operating system is: MacOS High Sierra 10.13.6. I wanted to instal Turbo Tax 2020, but realized it required an OS of 10.14 or newer. Can this Mac Book accept a new OS and if so, what is the highest OS it can receive? If I can upgrade the OS, do I need to bring it to an Apple Store or can I do I it myself online?

Also we have an older Mac Book Pro 15" bought in 2012, Serial # CO***V35, that accomodates CD's which is what we have used in the past to upload Turbo Tax. Its operating system is also:

MacOS High Sierra 10.13.6. Can this older computer accept a new OS as well

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