I am new in the Linux world, I know a little bit of Ubuntu and nothing on Debian.
I have a system running Debian 9.8, it has two DVI2PCIe cards and Debian did not autoload the driver. when I installed the OS. The kernel is 4.19.0-0 and I cannot find a driver on your website for this kernel. What is the best way to solve this issue? Do I need to downgrade the kernel version?
Indeed, the 4.19.0 kernel was compiled in the release of the LTS build of Debian 10 (Buster), not Debian 9 (stretch), which is compiled with kernel 4.9. While Debian 9.8 appears to include an kernel fix, it is still compiled with 4.9. https://www.debian.org/News/2019/20190216
For your system to be compatible with the DVI2PCIe capture cards, you will have to either update to Debian 10 build using kernel 4.19.0 or install the 4.9 kernel compiled with the Debian 9 LTS release.