How to paint on plaster wall?

[user-xxx]

Im confused regarding primer!

1 Apply putty on plaster
2 Apply primer
3 Apply paint

are these correct steps ?

[Arib]

1. Apply Primer
2. Apply putty
3. Apply paint

That's the order painter is following in my house.

[user-xxx]

ok and which primer should be used for Alkali resistance
Dulux aqua prime (water based) or Dulux Prime on (solvent based)

Im sharing prices just for info purpose because i searched on internet but couldnt find prices.

Dulux paint wall putty 20L = 1750 RS - 200 RS coupon inside it
Dulux Gloss paint 3.4L = 1700 RS
Primer 1 Litre = 450 RS