Someone managed to access all my gmails and Hotmails and gained access to my online wallets and took $1000 in crypto from me

I woke up and tried to login on my online blockchain wallet and the password was wrong. I check my gmails trash bin and the email where the guy verified the login was deleted the previous night. Location was a VPN in Europe. I have 4 wallets and he managed to do the same to all of them all at the same time. He changed the emails linked to them and the passwords. I was on my computer at the time he was doing it and I saw nothing I have no idea how he managed to do this. Anyone know what I can do next time to prevent this? It’s kinda scary knowing someone had access to all my emails and such via /r/Bitcoin https://bit.ly/34ABhuL