What linux support MacBook Air 2020 Keyboard & Trackpad ??

I don't believe any current Linux distro has the necessary kernel version in the default release at this time. Ubuntu 20.10 may include a compatible kernel when it is released later this year, but I don't follow (or use) Ubuntu. From my understanding support for the newer Apple laptops with T1 & T2 chips was only added to the Linux kernel at the beginning of 2020 with kernel version 5.7. I have no idea if the MBAir 2020 is even supported by this Linux kernel.

Currently you will need to install Linux to an external drive using another UEFI booting computer (PC or older Mac) so that you can upgrade the Linux kernel to a newer version and make sure proper WiFi drivers are installed. Then you can try booting this custom boot drive on your MBAir to see what works and what doesn't work.

I don't recommend installing Linux to the internal drive of a Mac for dual booting macOS and Linux (or even Windows) as people always misjudge how much space to provide to each OS. Users get into trouble by resizing partitions and lose access to their data and end up having problems to reinstall macOS. I recommend you run Linux in a Virtual Machine where you will not damage macOS. If you insist on installing Linux on bare metal, then at least install Linux onto an external drive so you don't risk damaging macOS on the internal drive.

I only ever read about the support for recent T1 & T2 Macs (2016+) being implemented in Linux kernels starting around v5.6 or so which occurred at the end of 2019, but I have not heard anything more about the support or how it works. There really isn't much information regarding Macs & Linux.

Unfortunately I haven't had the time to upgrade the kernel on my external Linux boot drive since it involves recompiling it from source and it hasn't been a priority for me yet. I've recently seen where I can now access a pre-compiled v5.7 kernel so I may experiment with it when time permits or I just need to be distracted for a while, or if a need arises for me to test a newer Mac using Linux (this is usually what gets me to "find" time to update & test Linux on a Mac).

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