My mom died of brain tumor that was cancer, is it herietary and i also had melanoma skin cancer 3 years ago, does my chances increase because of it?

In general: Most primary brain tumors aren't hereditary. Do you know what type of brain tumor your mother had? Nonetheless my condolences about your mother.

Unclear: It is unclear how this is known to be hereditary. The place to start is meeting with a genetic counselor to understand the family history and any (?) testing (not always needed) that may be done.