Azerbaijani citizens can travel to Kazakhstan without a visa. Under the bilateral agreement updated in 2019, you may stay for up to 90 days on an ordinary passport; the period used to be 30 days. A valid ordinary passport is enough to cross the border.
An important nuance: no registration is required for stays of up to 30 days, but if you stay between 30 and 90 days you must complete migration registration with the local authorities. Failing to register on time can lead to a fine. Work and study require a separate permit.
Almaty is chosen for skiing and city breaks, Astana for business trips and conferences. There are direct flights from Baku. Viza.az plans the route and accommodation while keeping an eye on the 30-day registration threshold.