transition old quicken and old MacBook pro to new 2021 MacBook pro

I've been happily using quicken 2007 on a mid 2012 MacBook Pro (high sierra) for ages but now must upgrade to a 2021 macbook pro which won't recognize the old quicken software. Wondering whether to use an alternative to quicken at this juncture. Also having issues with quicken recently (won't save), data from 2 different files/accounts opening in the wrong account.... Does anyone have any sage advice for a non-techy person?

Thank you,

Lars