Welcome to Amiga.org!
If your A600 doesn't have a full 2MB of chip mem (graphics memory) then you can upgrade with the
A602 memory expansion. It will also give your A600 an A1200-style clockport header which opens other expansion possibilities (e.g.
Subway USB)
If you wish to add Fast memory you can upgrade with 16-bit
SRAM memory cardHope this helps!