These days many new crypto coins and tokens are being introduced and It makes a very difficult decision for the investor to choose which coins or tokens should they invest to make some good profit.
Just focus on the top coins or tokens in terms of market cap.
Why make yourself stressed if you can lessen it by just investing into top coins. If you don't want to get stressed, just focus on buying Bitcoin. Stress makes a person older.

Many of the new cryptocurrency makes a good pump in their starting days and after on, they dump in a very dramatic way. This cause a very big loss to the investors and the trust in these types to new coins and tokens is finished.
A very common scenario that happens most of the time to the new coins that are being listed on exchange.
What's worse is that there are some coins that just being listed on an exchange, and after a few minutes after it being listed and can be traded already, it already dumped until it doesn't have any value anymore. No pump, just dump, dump and dump.
So, the main question is that Is it risky to invest in new crypto coins/tokens? or it is good for a very certain time of investment?
You're on cryptocurrency where investing into it is very risky.
Whether you are investing on top coins or new crypto coins or tokens, they are all risky. It all depends on the level of risk a coin/token has. Top coins have lesser risk. Those that are below top 100 on market cap has moderate risk, and those new crypto coins or tokens that are you are saying has the highest risk. On the other hand, there is a famous quote that says "The higher the risk, the higher the reward."
The most important thing is that you need to understand it, it is desirable to have an education in finance, it is not for everyone.