How to "book" and display other user's post in another view only for the user who clicked on a button or ActionLink in MVC C#?

Question

This is the model UserPosts.cs:

public int Id { get; set; }
public string Destination { get; set; }
public DateTime DepartureDate { get; set; }
public string Meetplace { get; set; }
public byte NumberofSeats { get; set; }
public virtual ApplicationUser User { get; set; }
public string UserId { get; set; }

This is the Create method in the controller:

public ActionResult Create()
        {
            return View();
        }

        [HttpPost]
        [ValidateAntiForgeryToken]
        public ActionResult Create(UserPosts userposts)
        {
            var userId = User.Identity.GetUserId();
            if (ModelState.IsValid)
            {
                userposts.UserId = userId;
                _db.UserPosts.Add(userposts);
                _db.SaveChanges();
                return RedirectToAction("Index","UserPosts");
            }
            return View(userposts);
        }

This is the Index view:

@model IEnumerable<Carpool.Models.UserPosts>
    @{
        ViewBag.Title = "Index";
        Layout = "~/Views/Shared/_Layout.cshtml";
        
    }

    <h2>All posts</h2>

<div class="allposts">
    @foreach (var m in Model)
    {
        <div class="posts">
            <table class="table">
                <tr>
                    <td><b>Destination</b></td>
                    <td>@m.Destination</td>
                </tr>
                <tr>
                    <td><b>Departure Date</b></td>
                    <td>@m.DepartureDate</td>
                </tr>
                <tr>
                    <td><b>Meetplace</b></td>
                    <td>@m.Meetplace</td>
                </tr>
                <tr>
                    <td><b>Number of Seats</b></td>
                    <td>@m.NumberofSeats</td>
                </tr>
                <tr>
                    <td>                        
                    ------>Here I want to add an actionlink/button<------
                        }
                    </td>
                </tr>
            </table>
        </div>
        <br /><br />
    }
</div>

What I want to do is: when the user who is logged in click the actionlink or button that is displayed for every post I want to save that post in another view only for that user who clicked it and in that view I want to save all posts when the user click on the actionlink or button. When the user click on the actionlink or button I want NumberofSeats property to decrease with 1. Please help me, I am trying to do this for some days and I haven't found a solution yet. Thank you!