The provided string appears to be a base64-encoded JSON object. The vmess:// prefix suggests that it's a Vmess protocol link.

Here's how you can decode and extract information from this link:

1. **Decoding the base64 string**:

First, we need to decode the base64 string using a base64 decoder tool or library. You can use online tools like [base64decode.org](http://www.base64decode.org) or libraries in your favorite programming language (like Python's `base64` module).

Here is how you might do it with Python:

```python

import base64

# The encoded string

encoded_str = "eyJhZGQiOiAiMTA0LjIxLjQuNiIsICJhaWQiOiAiMCIsICJhbHBuIjogIiIsICJmcCI6ICIiLCAiaG9zdCI6ICJnbHdlaWRmLmNmZCIsICJpZCI6ICIxMDUyZjI0ZS03YjA5LTQ1ZWItYjBjNS1kODU4ZWIxMjQxOTIiLCAibmV0IjogIndzIiwgInBhdGgiOiAiL2xpbmt3cyIsICJwb3J0IjogIjQ0MyIsICJzY3kiOiAiYXV0byIsICJzbmkiOiAiZ2x3ZWlkZi5jZmQiLCAidGxzIjogInRscyIsICJ0eXBlIjogIiIsICJ2IjogIjIiLCAicHMiOiAiXHVkODNkXHVkYzQ5XHVkODNjXHVkZDk0IEB2MnJheV9jb25maWdzX3Bvb2wifQ=="

# Decode the string

decoded_json = base64.b64decode(encoded_str).decode("utf-8")

```

2. **Parsing the JSON object**:

After decoding, we'll have a JSON string that we can parse into a Python dictionary using the `json` module.

```python

import json

# Parse the JSON object

data = json.loads(decoded_json)

print(data)

```

3. **Extracting Information**:

The decoded JSON object contains several key-value pairs related to the Vmess protocol. Depending on your interests and needs, you might be interested in extracting specific information from this data.

For example, if you're interested in the `server` address, you can access it using `data["server"]`.

Please note that understanding what each field represents requires knowledge of the Vmess protocol itself. The fields include things like:

- `server`: The server address.

- `id`: An identifier for this link.

- `alterId`: An alternate ID used in some cases.

- `tls`: Indicates whether TLS should be used (in this case, it's not specified to use or not).

- `ws`: Whether WebSocket is enabled (similarly, not specified here).

- `pType`: The protocol type (not explicitly mentioned but might imply HTTP).

- `host`: The server host.

- `aid`: The ID of the server.

- `netType`: The network type.

- `type`: The Vmess connection type.

To get the most out of this analysis, you'd need to look into the specifics of the Vmess protocol and how these values are used.