You can't avoid spam but you can filter it so it goes straight to your junk folder by setting your safety level to 'Only people in my contacts list'.
The problem with this is you have to check your junk folder if you are waiting for something from someone not in your contacts list, such as a hospital appointment which may use different email addresses for different departments.
I would rather not have to waste my time doing that, I have much better things to do - so only senders of valid emails get my email address.
A few years ago, subscribed to Talktalk (Tiscali), TT managed to have their customer database hacked, which resulted in their customers being flooded with spam emails and phone calls. I had so many spam calls per day, I had to buy a caller filter which eventually reduced the calls to almost zero, but the spam emails still flood into that account - when I can be bothered to check.
So I don't take kindly to misuse of my phone number or my email address.