yes you can....depends on what you want to do
you can fold under one name or different names or different teams
if you fold under the the same name, use a passkey
as you can see I fold for two teams and I have multiple computers set up to fold under my name (even for one team)
laptop don't do well for folding. it generates lots of heat and draws lots of power (not usually good for laptops)
yes you can fold on them , but they usually won't put up the numbers a good desktop system can
lappies usually don't have a good discrete GPU and usually a low end processor (just SMP)
depends on your laptop specs
others like madrias fold on lappies...they should be able to fill you in more there