I have a head Cold how Can I prevent an exacerbations

Head cold two days..
Has not gotten to a cough or lung stage..
Any suggestions so it won’t evolve into an exacerbation..
Only using O2 at nite at level 2..
Go up and down 32 steps To go in or out of condo
I have had TWO EXACERBATIONS..
One was with COVID..
YES I had flu/RSV SHOT..
ODIMETER reading 96-97