I have a Roth Ira and I am focusing on 5G. I can contribute $7,000.  How many etfs is to many?  I have 10. I have $5,000  left to invest.?

You need a single s&p 500 index fund.

https://www.businessinsider.com/personal-finance/w...

Depends if your ETF is already diversified or not. I diversify into different stocks and have done so for 20 years, but if you dont know anything about stocks then a low cost S&P index fund is something anyone can do with zero knowledge, and diversified because it trades with the S&P.  Do you think the S&P will be higher then now in 10 years?  Most likely.  Dont buy all at once, plan on 3 or 4 and buy on down days to get a better overall price.  Thats my 2 cents :)

I would not invest in technology for a retirement plan. Reason being that it changes too fast and is replaced too quickly by New technology. 

I would rather go for tried and true Blue Chip stocks in companies that have been around for a century or more-who pay a dividend i can reinvest. 

I am focusing on ice cream shops.   How many ice cream shop ETFs are too many?

Maybe if I like ice cream shops that much, I should look at the industry, do some analysis and choose the ice cream shops that I think have the best growth potential.

And maybe I should invest in some companies that aren't ice cream shops.

For someone with your inability to write a comprehensible sentence and doesn't appear to understand the stock market?  1 ETF is too many.

5G as in networking? Contributing to a Roth IRA for retirement is a good idea. Concentrating it in narrow investment "bets" is not so much.