Hello @loreennaa :)
for using steemfollower.com, you need to enter only your posting private key at steemconnect.com.
steemconnect.com created by busy.org. and you will only enter your posting key here.
you can check source code here : https://github.com/busyorg/steemconnect/
after login, steemconnect will warn you about what are you doing, vote and follow access which will only work with your posting key.
Remember, steemfollower.com is not bot, users will upvote eachother.
if you have any question about security, please check my last posts. I will never risk on steemit users accounts.
edit:
Also, about 5% referral bonus. it will not be sent to your steemit account. 5% bonus point will be converted to upvote to your posts.
when you upvote a post, you will receive some point based on your steem power and voting weight. at the steemfollower, you can see this point as Pending upvote SBD amount.
your post will get this amount of upvote from other users.
here is a video:
https://steemit.com/steem/@mahdiyari/video-how-to-use-steemfollower-com-an-upvote-and-follower-exchange-system-for-steemit-com
anyway, I hope you understand me :) goodluck.