I've been at Catholic weddings where there's Mass and Communion, but this hasn't been the case at any Protestant wedding ceremony I've been to. Although this may be different in a very 'High' Anglican church, communion is not normally part of a Protestant wedding.
If there is communion in a service which a lot of non- churchgoers are likely to be attending, the officiant will normally give some guidance- eg, ' come up and receive communion, or if not eligible, come up and receive a blessing'. Either way, there will be people who don't go up for communion, and no one will take any offence.
But in general, the CoE welcome all confirmed members of any Christian denomination to take communion, so it would be up to you whether you felt you wanted to or not. If you'd rather not, you can still go up for a blessing - just don't put your hands out to receive the communion and the vicar will touch your head and bless you. Or else just stay in your seat - lots of people will be doing that.
The only weddings I've been to where anyone took communion, it's been bride and groom only, but I remember only two if the many weddings I've been to where that's happened. Usually no communion at all. Don't think I have ever been to a Catholic wedding.
But anyway, if the whole congregation did go up, I don't think they'd be bothered if you took communion, or just went for a blessing, or stayed seated and didn't go up at all, though individual churches could be different, I suppose.
There probably won't be Communion, unless you've specifically heard that there will be - it's not normally a part of a Protestant wedding.
However, if there is, then it will most likely be open to everyone in the congregation. The Roman Catholic Church, I believe, forbids its members from receiving Communion at any other church, but Protestant churches allow anyone to receive it, generally (there are a few denominations that don't, but they would be particularly unlikely to include it in a wedding anyway), so it's up to you.
If you do find yourself receiving Communion, just make sure you're not first in line, and then you can copy the person in front. You'll be given the bread first (generally eat it straight away, unless you're specifically told to wait), and then the "wine" (probably grape juice), which again you drink straight away. Say "Amen" on receiving each one. The wine might be in a tiny glass, or a large communal cup - if the cup, you take a small sip and then pass it back.
Agree with pp - there will almost certainly not be communion (and you won't believe how short the ceremony is compared to a full nuptial mass!). You would be welcome to take communion but I believe most practising Catholics wouldn't.
However, I've never been given grape juice in an Anglican church?! It's always sweet wine, and quite potent.
As a rule of thumb, Catholic Churches don't recognise Protestant people but Protestant churches recognise catholic people. There are some odd and more 'devout' proddy churches I'm not familiar with but typically Protestant churches welcome anyone to take communion as their own choice. Catholic Churches mostly won't offer to protestants.
There won't be communion Protestants will either welcome all to communion. Or all who usually receive at their own church (but it's up to you to decide if that means you). BUT Catholic rules say Catholics should not recieve in a protestant church.
The reasons communion is not open to all at Catholic churches is Catholics and Protestants have very different beliefs about communion. The same for Orthodox congregations - Protestants should not receive at an Orthodox church. That's one of the reasons Protestants started their own churches because they rejected the Catholic and Orthodox teaching on communion.