I need to test my soil. Any store bought kits worth buying?

Is this soil test kit adequate for help to get my garden up and running?
https://www.menards.com/main/outdoors/gardening/lawn-plant-care/compost-soils-amendments/soil-test-kit/946/p-1444438486198.htm
I don't know what is required to test for.

Don't waste your money on that. Spend another ~$3 and have your soil analyzed by pros.
https://ag.umass.edu/soil-plant-nutrient-testing-laboratory/fact-sheets/sampling-instructions-for-routine-soil-analysis

That kit only tests for the bare minimum water soluble nutrients PKN, not a whole lot of use to you.
For around 15 dollars you can get a good soil test through your local extension service.

Can we back up a bit?

Why do you write that you need to test your soil? I'm not questioning your judgement, per se. But, why you think you need to test your soil might give us all better insight into how to answer your question most effectively. I would ask myself lots of questions about the local environment, what's currently growing where you will garden, what you want to grow in your garden, what resources you have to apply to this endeavor ... lots of questions before I would jump to soil testing. Maybe you already know all these things and have answered them in your mind and you still want to soil test .. rock on.

Grew strawberries in a raised bed with good soil. Had great berries for 2 years and then squat. Started a garden. Transplanted the berries. They are doing lousy. My peas and beans never got big. Mellons seem to be doing fine and corn (my first ever) is about half and half good and bad. Heights range from 18 inches to 7 feet. This garden is in a built up back yard from the 1980s. It sits near a septic field and I think it sets on a clay berm along side of the field. I have about 3 inches of top soil. I tilled it and added about 12 wheelbarrow loads of compost to the 20x40 garden area and tilled again.

I made a mistake with a garden once and I wonder if there are similar symptoms here. Are you absolutely sure the compost was finished? I ask because I mistakenly used a large amount of compost in a top-soil mixture (50-50 mix) on top of a new garden site. The foliage grew like crazy but the “fruit” part of the plants were pretty disappointing. I later figured out that because the compost wasn’t finished, I had an excess of nitrogen and too little calcium.

Strawberries: If by lousy you mean small fruit, then you may know you have a calcium deficiency. If the foliage is not doing well, then you may have a nitrogen deficiency.

Sweetcorn: Corn is a heavy nitrogen feeder. It’s the very reason why farmers rotate beans before planting corn. You may have a nitrogen deficiency where some of the corn is planted.

Beans: Very intolerant to salinity in soil and water; very sensitive to pH<6.0. Mg deficiency may occur in acid soils while being picky about micronutrients: sensitive to excessive Boron and to deficiencies of Copper, Molybdenum and particularly Zinc.

Peas: Needs well-drained soils and pH between 6 and 7.

I provide all this info because you can figure out what your soil is all about by what’s happening with the plants without going to the trouble of soil testing. You’ll also want to understand whether the test you may order is assessing plant-available nutrients or just the presence of them in the soil (two different things).

There are a host of websites and books that can help you identify each of the signs for each of the plants you’re growing to tell you what’s going on. Just like a doctor figures out what’s wrong with you based on symptoms, we can assess the symptoms and signs to know what may be happening with plants and the soil they’re in.

A 20’X40’ garden is a tight space for lots of different nutritional needs you’re asking the soil to produce. Having a strong handle on companion plantings for what you want to grow can also be helpful.  Just a suggestion.

Hope this is helpful. This is all based on assuming that the plants are receiving the required sun and water needs.

Why you need that soil test: I did one once send it over to you guys and paid a LOT of postage (still cheaper than to do it here). Applied the stuff needed and I had the first time that cabbages actually formed heads! That's why you need a soil test. There is no way of guessing, and there is no government agency anywhere around which would know what's usually in the soil.