Yes, you can purchase multiple plans at a time, Infimobile allows you to purchase multiple lines at the same time.
Go to the Plans Page
Choose the plan duration, select the desired plan, and click on "View Details"
Check your area coverage by entering your ZIP code, and verify your device compatibility by entering your device's IMEI number
Change the plan duration, choose the addons if needed, and click on the "Add to Cart" button
Complete the signup process if you are a new user, or log in to your account using your login details
Add more plans to the cart page or purchase multiple lines simultaneously from the cart page and click on "Checkout" button
Enter your shipping and billing addresses, and payment details, then click on the "Place Order" button to complete your order