Sia daemon has had skynet support ever since version 1.4.3, there's a package on Debian 11 known as "sia" which installs both siad and siac, problem is, those are version 1.3. You may install manually tho, download for Linux, unzip then move the binaries to
/usr/bin. Make a folder as working dir and setup a
systemd service too, if you're using Debian which they recommend. Change ownership of working dir to user
sia and no group.
After launching the daemon, letting it sync and create a wallet with some funds in it you can use
siac skynet upload [source] [destination] where source is the file and destination is the local cache dir I guess. Either way you may need 100GB of disk space for this setup, but it should be alright. Skynet and sia now does renewals on chain so your node doesn't need to be up and running at all time.