Welcome to the forum.
The bit you posted is for making T-Slots and is not something that will work with the Maslow.
You should look for 1 or 2 flute, up- or down-cut bits. The shank size should match your router collet, the cutting size depends on what you want to cut.
Go for cheap bit for the start, as you might burn some in the learning process.
Maybe something like this:
https://www.aliexpress.com/item/5pcs-6mm-1-4-High-Quality-Carbide-CNC-Router-Bits-One-Single-Flute-End-Mill-Tools/32363528604.html?spm=a2g0s.13010208.99999999.266.2f263c00GOSyPS
A video comparing bits: