Suppose If user gives bounty for another user's question then user is removed or is suspended for some period then will given bounty rolled back from that user's account? If user suspended for some period and given bounty rolled back then after that period will given bounty rewarded back?
No. Bounties are not refunded when a user is suspended, deleted, forgets they offered a bounty, finds the answer themselves while waiting for someone else, realizes bounties are not a way of awarding answerers a famous British ship, or runs out of paper towels.
Under normal circumstances - that is, those involving on-topic, answered questions - bounties will never be refunded. If you're not comfortable with this, don't offer bounties. It's a completely optional feature.
In very, very rare circumstances, moderators will opt to cancel a bounty and refund the reputation paid to offer it. These mostly involve questions that are a bad fit for the site and must be closed, migrated or deleted.