Email list

I’ve started my business as a life coach for small animal vets in September 2017 after joining SCS. I have constantly growly business and was accepted in the training program to become a certified life coach in August-September. Tjo-hooo.
I want to slowly continue building my business and manage my mind around this until then, taking steady baby steps. 🙂
Problem: I need to focus more intensively on building the email list, but approx. 33-40% of the subscribers are not confirming their emails, which is a LOT for a minuscule list. 🙂 I know that those emails are in their SPAM folders, and that’s why is more elaborate to be on the email list. I have Aweber (followed by the letter your 14 Steps 😊 ).
Should I just go on with my plans on catching people emails by going BIG and ignore the loses or are those percentage too high and I need to do something about it? What to do? I have no previous experience about being an entrepreneur/dealing with the tech-stuff, I was until September “just” a small animal vet. 😁

Thanx for the help that I am constantly getting from all of you! ❤
Loots of love to you!