The process for using this xylophone with your DAW or MIDI controller will depending on your computer's operating system. BLE MIDI is supported natively in macOS. Apple has great instructions on how to easily connect your BLE MIDI peripherals here.
On Windows, there is a little more setup involved. In order to have your DAW or USB MIDI controller connect, you'll need a software bridge to connect the ItsyBitsy to your desired MIDI input. There are a few available, but MIDIberry is a freeware option that is available through the Microsoft store. It allows you to select the input, output and monitor the MIDI messages being sent.
If you just want to play your xylophone live, then you can use MIDIberry on its own to control it. However, if you want to send MIDI out from a DAW for the xylophone to play for recording or live purposes, you'll want to setup a virtual MIDI loopback.
Most DAW's look for a MIDI hardware connection to assign MIDI input and outputs. By using a virtual MIDI loopback, you can trick the DAW into thinking you have different MIDI hardware devices plugged into your computer or even give your MIDI hardware extra functionality.
One of the most common solutions for this is the loopMIDI project by Tobias Erichsen. It allows you to easily add virtual MIDI loopbacks on the fly.
In MIDIberry, you can define the virtual loopback as an input with the ItsyBitsy as an output. This means that there is a virtual cable connecting the two together, allowing the ItsyBitsy to receive MIDI data from a DAW over BLE.
You can setup a MIDI track to send MIDI data out to the virtual loopback and your xylophone should begin playing along.
Playing the xylophone live with a MIDI keyboard is very fun and can allow you to play pieces that previously would've been impossible when limited to four mallets; especially on a bell kit/glockenspiel.
Taking in MIDI data from a DAW is really where things get interesting though, since you can record music live that previously would've been through a software synth. It could also make be a great addition to a live music setup whether it's for a traditional duet or for electro-acoustic music.