If you haven't already blundered onto the Palnet discord there's a great place to get help XD (and be further overwhelmed by the size of the server XD)
You said you were using SteemPeak? (I'm on SteemPeak's response page atm so not looking at the rest of the thread and I really should click on it to check but I'm laaaaaaazzzzyyyyyyyyyyyyy) If you are steemit is the original front end for steem and I don't like it very much so nothing to worry about at all if you're using another one you like more.
The percentage with the upvote is basically you can give 10 (I think) full powered upvotes a day before your vote value starts decreasing, so what a lot of people do is reduce the percentage so they can throw around more decent sized votes rather than 10 huge ones and then several smaller ones. If you haven't bought more steem then you're going to be giving "dust" votes anyway so don't worry about this just yet.
If you have bought more (or you are super patient and build your way up) then you'll see the vote value changing as you move the slider around and you can use it to work out precisely how much steem you want to drop on a post.
Clear as mud? :)
In the not too distant future you'll get to learn all about scot tokens and SMTs too yay XD
