BetChan did a really great job making up its bonus page. Currently, the welcome package contains 4 deposit bonuses up to 400 EUR + 120 free spins that you can spend on different releases. They all work in the same way, and therefore it makes no sense to describe each of them separately.
In short, you need to make a small deposit and then enter an appropriate promo code to activate any of the offers. The money will be transferred to your account instantly, just like the free spins.