How to troubleshoot a regularly crashing Google Play?
When installing Open GApps on Lineage OS, it must be flashed together with the Rom. Installing GApps after flashing the rom and booting the phone cause crashes. If you want to use Open GApps with Lineage OS, download both and place them in the memory and first flash the rom zip file. Without exiting the rom flash GApps zip and boot the phone. At the firts boot, you will be asked to configure your google logins and then GApps can be used.

Read installation instructions on LineageOS wiki