Well, there is a lot of ground to cover here. Okay, I will go in order of your post. First, if you have an iphone, get the gardnate app. It tells you what you can plant, when. It is good that you are starting to garden now, because if we ever get to where we have to survive off our garden, a lot of people will starve. I have been gardening, organically with heirlooms, for several years. A lot of stuff goes wrong and it isn't as simple as dirt water and sun.
Ph is important in most regions, but I have never really worried about it here in Nebraska. The soil is pretty rich around here. The clay can be combated with sand, but I suggest you keep doing what you are doing, with the compost. You may want to compost separately from your bed, however. That is not paramount, but it will compost better and then you can mix it in with your tilling.
Go get some of those little greenhouse flats. They have the transparent plastic lid to make miniature greenhouses. I already have Kale and parsley up. I have peppers planted but they have yet to sprout. This is just as expected. Some plants just germinate and sprout faster than others.
Also, some things shouldn't be panted next to each other and some things should. Plants love Nitrogen and some plants, beans in particular, are nitrogen fixators so other plants thrive around them. In your garden, surround the perimeter with garlic and onions. Also, marigold flowers. These things will help to keep some pests at bay. This is all called companion planting. You can find volumes of info on this and it gets confusing, the app helps.
Okay. Lastly, use Heirlooms. Most seeds and plants you buy at the store are hybrids. They cannot usually reproduce for more than one or two generations. Then they will either die off or revert to one of their parent varieties. If you use Heirlooms, you can save the seeds, and they will be reproducing for your grandkids without ever having to buy another seed. That is part of the problem that seed companies have with heirlooms. They lose their customer base after the first purchase. Therefore, the heirloom market is seek as kooky and is marginalized. This makes heirlooms harder to find, but several companies specialize in only heirlooms. I buy from Heirloomsolutions.com but there are many out there. Also, there is a seed swap every winter, but it has already passed this year. It is usually at Meadowlark Coffee on South St.
Okay, that is the 30,000 foot view of gardening. PM me if like. Best of luck. Gardening is a very rewarding, yet frustrating, hobby that might just save your life, so it is virtuous is my opinion. Let me know if I can help