Help with custom rom for Lenovo A7010

[amm2100]

I have Lenovo A7010 the 2GB ram version, it has been a while since I used it but I must use it now for a while until I can save enough money to buy another one so I wanted a light custom ROM to install it on it because the updated version of the stock ROM take 80+% of the RAM all the time so it freezes all the time
any suggestions ?