How to send MATIC to MetaMask
Get free MATIC
At the time of writing, you could receive 0.001 MATIC (enough for several transactions) on the Polygon network when you connected your MetaMask wallet on this website https://matic.supply/
If you cross chained to the Polygon chain for the 1st time, you may have received some MATIC for a few trades, check the conditions on the ZeroBridge page.
And if you crossed chained ZERO, swap some ZERO for MATIC if you want to have a bit more in reserve.
Buy MATIC on a CEX
For the withdrawal from these CEX, there is an option to withdraw directly to the Polygon network configured in MetaMask.
Although as usual, Binance may temporarily disable the withdrawal. In that case, send USDT from Binance to Ascendex via the TRC-20 network (free and fast).