I wasn't able to find time to update Safari for my MacBook13.1 and now I cannot get into my bank account could you help me

See the following from Update or reinstall Safari for your computer - Apple Support

• To keep Safari up to date, install the latest macOS updates. The most recent version of macOS includes the most recent version of Safari.

What model of Mac (e.g., iMac, MacBook Pro, MacBook Air, etc) and what model year do you have (both are available at Apple menu > About This Mac)?

Sometimes doing an upgrade to Safari still will not wok with some web sites. Then the problem is usually solved by installing and using another browser such as Firefox or chrome. They usually work just fine. That is why many of us use more than one browser.