The problem is that the people sending the emails will continue to send them to the old email address so you never solve the problem.
You will need to contact the people who send the emails and tell them of your new address. If the emails are coming from web sites then you will need to update your contact address on the web sites.
By the way, it is not a good idea to have just one email account and it is far better (and safer) to have multiple email accounts.
If you have only one email account and someone finds out your email password, then they have access to ALL the emails you send and receive and all the people you have contacts for.
Also if you start getting spam it will all go to the one email address.
The other problem with having one email account is that ALL your mail, important and non important, goes to the one place and you have to sort through it all to find the important stuff.
It is far better to have a number of email addresses:
1) One email address you ONLY use for friends and family. Never use it to register for web sites or use it on public forums.
2) Another one or more email address for your "junk mail". It get mail from Amazon, Tesco, Argos, Nectar and dozens of other web sites. I send these all to a couple of gmail addresses that I use for nothing else. Because it is not important mail I can logon to these every few days.
3) If you do banking keep one email address JUST for banking.
4) Also have one "throw away" email address you can use for quizzes or special offers. Then if it starts to get spam just delete it and create another one.
Also be wary of deleting old email addresses till you are certain they get no more email. I usually keep an old email address for a year before I delete it to make sure no emails are going to arrive, it is amazing who can have your old email address and still use it, someone you have totally forgotten about.