As documented:
https://api.twitch.tv/helix/users/follows?to_id=user_id&first=1
curl -H 'Client-ID: uo6dggojyb8d6soh92zknwmi5ej1q2' \
-X GET 'https://api.twitch.tv/helix/users/follows?to_id=user_id&first=1'
In your paste you have a -s for some reason, and lacking a space between client-id: and the client_id.
You seem to have something else going on causing an issue due to
‘firzst’ is not recognized as an internal or external command,
operable program or batch file.
is off output for cURL