I am a new graphics designer I want to use skull head, spoon icon, fork, etc in my logo from free stock but I don't know how to avoid copyright issue
1If you wish to "avoid copyright issues" never use stock images. And most, if not all, stock image sites expressly forbid use in a logo unless all rights have been purchased.– ScottMay 15, 2019 at 16:47
If the shape is so innocuous and plain that you feel it's merely a nondescript "icon" then simply draw your own. A "spoon" or "fork" could simply fall into that area. A "skull" would depend a great deal upon the artwork itself. In many cases, a "skull" may be too unique to be classified as a general "shape".– ScottMay 16, 2019 at 23:39
Simple answer: don't use other's work in any logo you design - yours or a client's.
That will avoid any copyright issue.
However, also bear in mind that a "derivative' work, at least here in the US (and I believe in UK & EU, but others will have to verify) doesn't have to start with a literal copy: if you copy the design intent, the idea, the visual concept, and execute it yourself, you can still be at legal risk.
Put it another way away from the legal nonsense - why would you want to use someone else's work for your logo as a designer anyway?