Advice for beginner

Hi folks, ​ I am 45 and I want to diversify my investments. My target is to have some cash for when I retire to support my pension. ​ I am already investing (passively) in stocks: I have accumulated around 220k through my job (stock rewards). Everything is in one stock. ​ I am now looking into ETFs to add to my portfolio - VWCE specifically. ​ My question is the following: ​ I have some cash in a bank doing nothing. Do I just put them (- my safety net) directly into VWCE? Should I get more than