Metamask WebApp Integration

Hello Developers! Our decentralized community is launching a token on Polygon to facilitate our trust and trade between members. To do this we need to integrate a wallet, preferably Metamask, into WEquil.App which is a Flutter based WebApp. We are building out the incentives structure for the token ahead of our launch in a couple weeks, and would prefer to do so in a way that would allow our test token logic to migrate to these wallets. Happy to learn from those with experience integrating a Metamask wallet into a WebApp. Thank you!