trying to make a staff 1d8+4.. +6hit

I know where d8 goes

where do +4&&+6go

You cannot make a separate bonus to attack and damage. Please see the Items & Equipment FAQ #9* for more information.

And a staff automatically does 1d6 (1d8 [worop]versatile[/wprop]) damage, there is no possible way to change that. Please see the Items & Equipment FAQ #1* for more information.

*(https://www.dndbeyond.com/forums/dungeons-dragons-discussion/homebrew-house-rules/131411-a-homebrewers-how-to-faq).

it's a custom made staff

+4hit

d8+3

I understand that, what I am trying to tell you is that it is not possible to make that on this website. The Staff will always automatically default to 1d6/1d8, and the best you can do is +3 to both Attack and Damage rolls. Essentially the closest you can get it is the same as a Quarterstaff, +3.