I just installed Mojave on 11-inch MacBook Air bought in 2014, and it now crashes every 5-10 minutes

Hello:

I have the following computer:

11-inch MacBook Air bought in 2014

With the following configuration: • 1.4GHz Dual-Core Intel Core i5, Turbo Boost up to 2.7GHz

• 8GB 1600MHz LPDDR3 SDRAM•512GB PCIe-based Flash Storage

I just installed Mojave 10.14.6 yesterday, and now the computer shuts down (crashes) and re-starts every 5-10 minutes, which obviously makes it useless, so I desperately need help.

Please.

Thank you,

Peter