Can I hold my 4 day old kitten my cat just had 5 of them and they are so cute but I want to hold them and I'm not sure if I can.

No you cant hold them. Just leave them alone until they are weaned by the mother.

To be good pets, all kittens require early-age socialization. The age when kittens are most receptive to socialization is two to seven weeks. Here's a site with helpful guidelines:

https://www.thespruce.com/reasons-to-socialize-kittens-553890