In case anyone is interested, I got a bunch of sheets to practice Chinese calligraphy from www.writemandarin.com and merged them in a single pdf file.
The sheets are free so cheers to them, I'm just saving you several clicks because in their web you have to download each one separately and the process is a bit tedious.
The link to the file: https://drive.google.com/file/d/1LlhcTUCEQhzFEXTFGc0-EBU7JUE27Sgw/view?usp=drivesdk
They look really cool if you print them and make an actual booklet!