android - How to show fixed number of items of rows in a recyclerview -

i'm trying menu footer have 10 button , can horizontalscroll.

so use recyclerview that. want footer default show first 5 items in screen screen size , user can scroll this.

so have question

1. how show fixed number of items of rows in recyclerview ?

2. how set distance of 2 items in list recyclerview ?

thanks read.