I'm a granddad I have the same problem. I've had lots of advice and still can't get it to work. The closest I got was to transfer the picture but not the sound.
I'm in Crete where the "experts" are not experts - just macho. Maybe you could get a grandchild to set it up for you (like we used to get them to programme the VCR)
You will need a bit added to your computer which is designed for TV programmes so you need a bit of help. Then there is the dreaded cable. Then there is the software. It's all in that new language that youngsters just know & which totally baffles me
Do you know there are companies that do it for you - I'm guessing but you could probably get up to 5 done for the cost of doing them yourself.
I'm looking forward to seeing what the real experts on this forum have to say - you certainly have come to the right place!