It turns out I may be in error. Depending on the type of arthritis you have, you may want to avoid spinach, aspirin, & even beer. My sister is in a similar condition as you, but her doctors never told her she couldn't drink alcohol or her wine. But it's probably not a good idea to excessively drink.
CoQ10 is good for the heart, ease or slows down the aging process, & may help a little with arthritis. It's severely lacking in older people. I've tried 100-200mg a day before with no improvement so stopped. But at 300mg a day the improvement was quite noticeable. If I'm having a bad day, I'll go up to 400mg a day... spread out no closer than 100mg every 5 or 6 hours.
Beet juice or beet juice powder will help give you energy & strength when you're weak. Beets won't work because heating kills all the most useful ingredients. Beet juice or beet juice powder has the most concentrated form of the good stuff, whole beets are weak by comparison. But it has to be added to cold or warm stuff, not hot or cooked, or warmed up. Warm up before adding it to foods, not after.
The vitamins & minerals in beets are common, & you can even get them in a pill. What you want in beet juice is the natural nitrates (not meat additive types), & natural antioxidants. It's more concentrated in the juice & juice powder, but heat destroys it. So if you add it to foods like soups & stews, you'll have to let them cool down to where they're warm, not hot before adding it.