Best immune support lyme bart etc...

I like Aswaganda and LDN to help with inflammation.
I hear medical mushrooms like Lions Mane work well too. Good luck

I have not heard of lion's mane used for immune support so much as neurological support. Lots of medicinal mushrooms are great for immune support, though, especially cordyceps and reishi. Host Defense makes some great blends, including one for immune support.

Also these come to mind:
liposomal vitamin C
vitamin D
zinc
selenium
adaptogens (eleuthero, ashwagandha, etc.)
elderberry
echinacea
manuka honey
probiotics

And I think it's important to keep from catching colds, flus, and other transient pathogens as much as possible. Eat at home, use utensils, keep fingernails short, wash your hands, shower when you get home from anywhere, clean things you touch regularly (door knobs, computer, PHONE, steering wheel, etc.), wear a mask at the doctor's office, drink from a bottle with a lid when in public, avoid crowds, and never touch your face. Setbacks from even a mild cold can be a big deal for folks with Lyme, so avoidance can give your system a big break.

Buhner recommends cat's claw, knotweed and for bart- rhodiola and ashwagandha. Cordyceps also comes up a lot. I personally can't take that because of MCAS so just fyi.

Also, intermittent fasting is great for gut health and immune function. I have poor adrenal health and can still do it on occasion so adrenal fatigue isn't always a halt to that