There are many networks available on Metamask.
Is there any difference among all these networks?
If i want to buy, send or swap any token, will it the matter for me choose any one network to perform the task?
Any significance?
Why are there so many networks?
IIRC, there are some crypto projects that create her own network on metamask for the usage of storing own coin as well having "only family" chain, examples of such coin was
E3token which have their own E3token network.
If you really wanting to find ERC20 token then it's advisable to use ethereum network, the first network at the select cursor. Therefore, you are selecting a network corresponding with preferred coin.