Keeping it simple.
To start with, find a quiet room, do use a head set with mic, and just start recording on your phone.
Sure, this is not ideal, but this is about getting going. I will say this often, do not let the perfect get in the way of the good. As you do this more, as you find you enjoy this, as you get over the cring of hearing yur won voice, so then you can invest in a better mic, find a better place to record, start edigint the recrodings.
But to begin with…. this is good enough.
The most important thing is that you use a recorder that records in MP3. And that you upload in MP3.
There are many audio formats, so take care to keep with this standard.
Apps for MP3
Computer (PC/Apple): Audacity, Website https://www.audacityteam.org/download/7/