Upgrade Old Snow leopard MacOS to latest OS without access to Apple ID
I got an old Mac Book of my uncle with Snow leopard which does not support most of the browser or website anymore. Did some Google to upgrade it and learnt that it first need to be upgraded to El Capitan and then to any latest one.
I am first time apple user so took some time to learn everything. When trying to upgrade to El-capitan, i am prompted for Apple ID and Password, which is not with me nor with anyone in my family anymore. I tried to create new apple ID but that also does not work. I read somewhere that new Apple ID won't help anymore.
Is there any way to upgrade and use my macbook or I should give up the hopes to upgrade?
I believe there has to be way, Apple is a huge organization and they certainly will have some ways to resolve this situation.
Seeking some help.
Regards,