As a new investor I will give you the decision to invest in Bitcoin. This is because the price of Bitcoin may rise in 2024. If you have 2 BNB's you can hold one BNB and buy bitcoins with the other. Because when the price of Bitcoin increases,the price of BNB also increases a little. Don't underestimate Ethereum,you can invest in Ethereum with 1 BNB if you want. If you don't feel confident to invest in one then you can invest in Ethereum,Bitcoin for a small amount. Best would be to invest in Bitcoin. Now decide which platform you want to invest in.