There is some saying about running with scissors. Windows 7 will not be getting any security updates after Jan 2020, so your computer will become vulnerable. 

Consider ProConnect Tax Online https://accountants-community.intuit.com/articles/1861899-system-requirements-for-proconnect-tax-onl... Internet based junior version of Lacerte. Since the data is online, there is a different vulnerability. 

If you are gutsy there are articles about doing the Windows 10 upgrade for free, just be sure to do a thorough backup before trying.  Even better and less risky, consider buying a refurb computer - I see some on Amazon for less than $100 that meet the minimum Lacerte requirements.