Sealer should help, Gloss is pretty durable if you let it cure properly before touching it
I'd still reccomend getting a tub of white (or black) acrylic gesso for priming.
They can be mixed with colours to make a tinted base coat, but I would reccomend having the mix mostly gesso.
Theyre incredibly thick, but do shrink as they dry.
So you can be somewhat sloppy with application (not too much though)
Liquitex do a nice gesso, Personally I use Windsor & Newton Galeria stuff as its cheaper where i shop.
I normally Spray prime though, only bother with brush on for a really fiddly small piece
tbh.
The Citadel Imperial Primer would be similar to black gesso I guess.
Should have better adhesion than just abbadon black atleast.