Posting here because my text post got removed

Quick question... a coworker/friend of mine (65 M) had his Thymus removed a month prior to the pandemic..

(I know nothing about medical issues and am asking for advice/support) hes fully aware of his past medical issues, and the seriousness of this situation, hes had his Thymus removed because it was attacking other parts of his body (part of an autoimmune disease he has).

The Thymus, from my understanding, is what produces antibodies in your body and yes he had that REMOVED. He’s been undergoing treatment to get his body back to a finite 100% by having antibodies pumped into him. He had finished surgeries and whatnot a 2 weeks- a month prior to the pandemic

He’s also had cancer in the past, clogged arteries, anemic, and other issues as well. he’s on the mend just before this pandemic happened. Genuinely asking for a friend, he is not leaving his house and has not left his house in over 2 weeks. What other precautions must he take? Could anyone with more info on something this specific please help? Thanks and god bless! Anyone with a medical background that can add any input is greatly appreciated.