Welcome to the forum @Kitt3n 
I think you might have copypasted the post as the system bot flagged it as potential spam, which happens when it thinks people types too fast; I have cleared that. 
So you’re learning western occultism, how long have you been practicing?
I’m not familiar with that spelling, do you mean Clauneck from the Grimorium Verum?
You don’t need a pact, and a pact is kind of a big deal. It’s ideal to just work with them first and build a relationship before betting in deep like that.
Not really, but it’s nice to follow a recipe that’s known to work for others, when you’re still new. Otherwise “Do as thou wilt shall be the whole of the law: Love is the law” … Do whatever you want to do.
You don’t need any offerings. I work with Clauneck and I have never given offerings except as thanks after results have manifested. I think you want to avoid an atmosphere of “payment”, they’re not merchants. But maybe that’s just me. 
If you’re talking about Clauneck, no he’s not into offerings, in my experience. He’s more like a way to manifest your will, so you working with his energy to get what you need IS the offering.
No. Sounds like something from fiction.
It’s ideal to work on your sensitivity and astral senses before diving in with contact. You also want to make sure you know how to keep your space clean and clear of unwanted energy that could interfere, how to banish and cleanse to fix a problem entity if it does arise, and how to check you evoked the right entity and not an imposter or parasite… These safety basics are talked about on here as well.
Here’s a bunch of info in a sort of getting started guide: look for the “spiritual hygiene” and “developing astral senses” bits
Ah, you’ve been reading the opinions of the religion called Demonolatry. It’s their opinion and most practioners don’t agree, it’s a very modern view and I find it a bit weak and insecure.
No, first of all the sigil is not “confined” the circle it t help you bring your attention to it. Second, I believe the entities have free will and don’t come if they don’t want to: they come because they want to. I realise Solomonic Techniques bother a lot of people as they don’t hold modern values and sensibilities, and they used to bother me, but I didn’t understand them, I has listened to hearsay of people that didn’t understand them. Learn from my mistake and study it well before making your mind up.
If any, doing it too soon, or, doing it by “going through the motions” when you’re not actually connected, and didn’t take the time to develop the skill to be able to tell, and you’re just talking to yourself, or worse to parasites.
Then don’t do it until you do. There’s a point where you have to just try something, but do not rush in without taking the time to understand the landscape, what’s real and what’s not. Especially into full on pacts, which are not necessary or advised. That’s 2 years down the line stuff. You’ve been reading too much fiction already and this is a good way to get into trouble.
The best advice I can give you:
- First and foremost, know thyself. This is a lifelong endeavor but is the most important. Meditate, build your energy and your sensitivity. You need it for everything, from recognising signs to sensing presences or gaining insights.
- Read real, time tested Grimoires that people have reported practicing with successfully. Know the difference between UPG (unverified personal gnosis) and verified gnosis.
- Read everything you can find about the entity before contacting. This is called “Preparatory immersion” in these parts and helps you connect faster and more easily.
You can also search here and online for the entity name to look for topics with people having issues or successes or tips with the entity you have in mind.
Clauneck is from the books: The Secrets of Solomon, Grimorium Verum and Dictionnaire Infernal. I’d suggest getting one of those for background. There’s usually instructional stuff earlier on in the book.