How to create my own "ETF" for a block trade of 100 shares across 20ish tickers.

My subject line might be a little misleading. I want to create a block of 20ish positions, with with each having between 2 to 16 % of the total. Each block would be 100 shares of the underlying stocks.

So one stock would be 2 shares, on up to the largest position being 16 shares. Then I would want to be able to just trade 1,2 or more blocks at a time, so that all of the underlying shares would open at approximately the same time, and when I want to close it, I could close all 100 shares at the same time, with just one entry, instead of having to open and close 16 different positions constantly.

Is there a may to do this fairly easily? I am not a programmer, but have been learning some AI for a while.