Using C# LINQ with MongoDB Find

Question

I am only about 3 days into using MongoDb and C# driver so be gentle. ;-)

I have a MongoDB query working with AsQueryable.

I would like to use the collection.FindAsync(Func) instead of the AsQueryable, but still passing in my own lambda express. This is because I want to abstract all the MongoDb into a library so that my app code doesn't know what DB I am using.

I am also not crazy about having a lot of methods for each collection. Also, AsQueryable isn't easy for async.

Suggestions?

Calling method

    bool CheckIfClassNumberExist()
    {
        var retCheck = _dbAccess.Find<ShowClass>(
            c => c.ClassNum == Model.ClassNum);
        return retCheck.IsSuccess();
    }

// Find method in DbAccess.cs

        public Result<T> Find<T>(Func<T, bool> func)
        {
        try
        {
            return TryFind();
        }
        catch (Exception e)
        {
            _logger.Error(e);
            return Result.Failure<T>().WithMessage("Not found!");
        }

        Result<T> TryFind()
        {
            var table = typeof(T).Name;
            CheckDb();
            var collection = _db!.GetCollection<T>(table);
            var query = collection.AsQueryable().Where(func).FirstOrDefault();

            //var query = await collection.FindAsync(func);

            if (query is not null)
                return Result.Success<T>(query);
            return Result.Failure<T>().WithMessage("Not found!");
        }

This doesn't compile: MongoDbAccess.cs Shared.MongoDBLibrary Argument 1: cannot convert from 'System.Func<T, bool>' to 'MongoDB.Driver.FilterDefinition'

        async Task<Result<T>> TryFind2()
        {
            var table = typeof(T).Name;
            CheckDb();
            var collection = _db!.GetCollection<T>(table);
            //var query = collection.AsQueryable().Where(func).FirstOrDefault();

            var query = await collection.FindAsync<T>(func);

            if (query is not null)
                return Result.Success<T>(query);
            return Result.Failure<T>().WithMessage("Not found!");
        }
    }