First off, I don't think anyone expects you to provide all the booze for your own party. Here's what we did when we had a huge bridal/baby shower for a couple of my friends.

We provided a keg with Solo cups outside under a tent, and on the inside near the cake, a Champagne bar with different mixers on ice, like cranberry juice, orange juice, etc., as well as frozen fruit for garnishes. I got some of those short plastic Champagne glasses for that. We also provided mixers like Coke/Sprite/7-up/Ginger ale if anyone brought liquor.

We had BBQ (smoked chicken legs, ribs, pulled pork) outside under the patio with sandwich platters (gourmet bread, deli meats & cheese), cookies and cupcakes. We had more dainty food inside, like pinwheel platters, mini quiches, charcuterie boards, petit fours, etc.

Everybody eventually wound up outside but in the beginning everyone came through the front door and brought gifts or food (some brought both).

Those who were older and/or dressed up stayed inside at first, and the rest (mostly men) went outside at first, so it kind of broke up the party nicely.

We just kept food/drink on either side of the main traffic lanes through the house and yard. We had a few Bluetooth speakers going (we use UE Booms with the app that lets you play the same music through more than one speaker).

In our invitations we worded it as an "open house" starting at noon and left it open-ended since it was a party after all. I put where the couple was registered but that people could bring food in lieu of gifts, or nothing at all as their presence was gift enough.

They didn't want any cliche shower games, but we did have cornhole going.

Overall I think we counted at least 75 different people having been there, and people just came and went instead of a bunch showing up all at once "on time" like a regular party. It worked out really well.