Researching the internet I have found two great tools that can be used for testing webapps and webhooks.
The first is called ngrok. What it does is that it creates a tunel to your web app and makes it accessible from the internet through https without port forwarding. It acts as a kind of reverse vpn but for https access only. Its link is the following:
ngrok.com
The second and also very interesting tool is beeceptor. It is a webhook receiver and post api receiver in order to check what various services will post to your webapp and create the receiving code correctly. Its link is the following:
beeceptor.com
They are free to try.
The first is called ngrok. What it does is that it creates a tunel to your web app and makes it accessible from the internet through https without port forwarding. It acts as a kind of reverse vpn but for https access only. Its link is the following:

ngrok | API Gateway, Kubernetes Ingress, Webhook Gateway
ngrok simplifies app delivery by unifying API gateway, Kubernetes ingress, multi-cluster load balancing and more with ngrok's Universal Gateway.
The second and also very interesting tool is beeceptor. It is a webhook receiver and post api receiver in order to check what various services will post to your webapp and create the receiving code correctly. Its link is the following:

Beeceptor - Rest & SOAP API Mock Server
Deploy a mock API server instantly. Build mock REST API and SOAP APIs without any coding. Inspect request and responses, HTTP debugging, intercepting and proxying. Best alternative to JSONplaceholder & Wiremock.

They are free to try.