you should not invest this much money in a market that you clearly have no prior experience in. jumping in like this will lead to massive losses and not just because altcoins get dumped but because protecting your coins (securing wallets,...) is not an easy task specially for a newcomers.
additionally if you look at the 10 year history of this market you can clearly see that investment in altcoins is never a good idea and even if it leads to long term profit it will be a very small profit compared to bitcoin profit.
an example with your numbers:
10 BTC - $70k
250 ETH - $57k
if you invested the $57k in bitcoin instead, this year alone would have given you $92000 profit but investing it in ETH this could only give you $10000 which means you would have lost $82000 because of a bad investment.
it doesn't stop there either. in the long run, like a year or two, bitcoin is going to continue rising while all these altcoins today will be worth a lot less.