Is it safe to use a custom startpage privacy-wise?

I love my custom startpage (I use Tilde, thank you person who made it!). But was often wondering, if it can be problematic regarding my privacy? Can websites see when I am coming from a specific starpage e.g. the "url" of it (/path to the html) or something?

Tried to search online but its difficult because I only get results about "the" startpage

privacy safe startpage