Here are a list of websites that will help you to remember past learning and to build upon your existing skills. Remember frequent practice will make you a more confident mathematician.
BBC Bitesize. If you need to remind yourself of the learning from year 1 then go back and start there. If your learning is secure then try solving some 'tricky' word problems using the knowledge you have learnt. Ask a grown up to help if you need some questions. https://www.bbc.co.uk/bitesize/subjects/zjxhfg8/year/z7s22sg
White Rose- This is the site we use in school. Watch the videos and complete the challenges.
Topmarks- A wealth of mathematical games and activities to practice your rapid recall and to help retain your learning.