Can we set up a referral campaign where our customers can share the link with their friends and get credit in their account, while their friends receive a discount they can use in our store?

Yes, that will be a Goal Based Rewards campaign.  The original participant will have to complete the goal to get rewarded (invite 1-10 friends to visit or convert on your website). The incentive for their friends will be in the form of a coupon. They will receive the link, click on it, see the coupon, copy it and proceed to your website. This is how it works in our system.