which paint for going over existing finish on bookcase with kids design

hi there i would appreciate advice on the following
I bought a secondhand solid pine bookcase which has some sort of varnish on it -a light matt one i think - probably acrylic
it has some scratches on the wood so i am sanding it down to get rid of those
i would like to either revarnish it or paint it but i am not sure what to use
if i revarnish it that seems straightforward and will probably take it remove all the existing varnish just by sanding (i think i need to do that to get a nice finish - not patchy - do i need to do that?) i like the look of natural wood with a clear finish (but not sure my son will prefer that!) so to make a nice design i think it's better that i paint it instead - so if i paint it then really i want to end up with a background colour for the design say white and then being able to paint a simple kids design on top - say stenciled alphabet etc
does it matter what i paint over varnish with ?
and what do i paint on top of the base colour with ?
i thought i'd use gloss but then i think the colours to go on top of that won't work ? ie will bleed or not endure
how do i seal in the design ?
it all must be very durable as it's for a kid's room
i think they are always doing this in those tv programs but i don't get what paints they use
i remember pva being mentioned - is it something to do with that
thanks for any help and advice on best shop to go to for this kind of stuff
i am a novice on all this
regards JD
please reply to group - and not email - as email is just a spam bounce - sorry to much spam from newsgroups
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You can get theme transfers for kids, that you'll be able to place over any bad patches on the unit, then apply a clear varnish over the top to seal them all in.
In the future, when the little one has grown out of the transfers, you sand off the seal coat, wet the transfers to peel them off, sand back the unit, then varnish it again to give you another lease of life out of the same piece of furniture.
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thanks i thought about that but i don't want transfers really

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