Opening a Douyin store and window display does not automatically open a WeChat merchant account. Although Douyin and WeChat are products of the same company, their merchant account opening procedures and regulations are different, and they need to be applied for and reviewed separately.

If you want to open your own merchant account on both the Douyin and WeChat platforms, you can follow the steps below:

1. After registering on the WeChat public platform and passing the review, you can open your own merchant account on the WeChat public platform.

2. After opening a Douyin store, you can apply to open a Douyin merchant account in the Douyin store backstage and submit relevant materials for review in accordance with the regulations of the Douyin platform.

3. If you want to conduct e-commerce transactions on both Douyin and WeChat platforms, you can consider opening your own mini program on the WeChat public platform and linking it with the Douyin store so that you can conduct transactions on the WeChat platform.

It should be noted that when opening a merchant account, you need to comply with relevant regulations and requirements, such as real-name authentication, qualification certification, etc., to ensure that your merchant account is legal and compliant.