Ethereum and Solana are two very good project, they're both blockchain projects that are leading in the creation of a good blockchain for other cryptocurrency to be operating on. Ethereum is old but still very productive while Solana is new and having some problem with their blockchain but they're always working to fix any problem that comes up. Ethereum is closer to fixing their high fee problem that made many developer to leave the blockchain before.

Solana has many projects using their blockchain recently to launch new projects and they're doing very well therefore they'll also be bringing new investors to the Solana blockchain. I think Solana will be a better project to invest into and you can make many profit as Solana is still low and not upto the last all time high. There's much room for growth for the Solana coin and the blockchain so I'll pick Solana.